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WorksheetsPhysics Midterm Review Questions
Total questions: 129
Worksheet time: 3hrs 32mins
Name
Class
Date
1.
A scientific law is best described as:
a)
An explanation of why natural phenomena occur
b)
A description of what happens in nature under certain conditions
c)
An educated guess that needs testing
d)
A proven fact that never changes
2.
Which of the following best describes a scientific theory?
a)
An educated guess
b)
A well-supported explanation based on extensive evidence
c)
A description of what happens in nature
d)
A proven fact that cannot change
3.
Convert 2.5 × 10³ milligrams to grams.
a)
0.0025 g
b)
0.25 g
c)
2.5 g
d)
250 g
4.
Which question can be investigated scientifically?
a)
What is the meaning of life?
b)
Is one culture superior to another?
c)
How does light intensity affect photosynthesis rate?
d)
Should we fund space exploration?
5.
A scientific theory is supported by:
a)
A single experiment
b)
Opinion of famous scientists
c)
Extensive evidence from multiple independent investigations
d)
Mathematical equations alone
6.
Scientists worldwide measure the speed of light and obtain consistent results. This demonstrates that:
a)
Light speed is the same everywhere
b)
Valid scientific methods produce reproducible results regardless of who conducts the study
c)
All scientists use identical equipment
d)
Light is the fastest thing in the universe
7.
A student claims astrology is scientific because it makes predictions about personality. Evaluate this claim using scientific criteria.
a)
Valid - making predictions is the key criterion
b)
Invalid - astrological predictions cannot be objectively tested or falsified through controlled experimentation
c)
Valid - astrology has existed for thousands of years
d)
Invalid - only physics and biology are scientific
8.
The Theory of Plate Tectonics is supported by evidence from fossils, earthquakes, and seafloor spreading. Why doesn't it become a "law" after all this evidence?
a)
Not enough evidence yet
b)
Theories and laws serve different purposes - laws describe patterns, theories explain mechanisms
c)
Scientists haven't agreed to call it a law yet
d)
It needs testing for 100 more years
9.
Ancient cultures believed heavy objects fall faster than light ones. Galileo challenged this through experimentation. What does this illustrate?
a)
Science is based on ancient wisdom
b)
Scientific knowledge can be revised through empirical evidence, regardless of how long a belief was held
c)
New scientists always disagree with old ones
d)
Heavy objects actually do fall faster
10.
Newtonian physics accurately predicted planetary motion for centuries. Then Einstein showed it was incomplete. Does this mean science is unreliable?
a)
Yes; changing theories prove science is unreliable
b)
No; science refines understanding with new evidence. Newton's physics still works perfectly for everyday situations
c)
Yes; we should reject all old theories
d)
No; Einstein proved Newton completely wrong
11.
A pharmaceutical company tests their drug and reports 95% effectiveness. An independent university study finds 60% effectiveness. What should a scientist conclude?
a)
Company study is correct because they developed the drug
b)
Independent replication is crucial; potential financial bias requires skepticism until more independent studies confirm results
c)
Both studies are equally valid
d)
Average the results to get 77.5% effectiveness
12.
A website claims "quantum energy healing" uses quantum physics to cure diseases but provides no mechanism or studies. Why is this pseudoscience?
a)
Quantum physics is too complex for medical applications
b)
It uses scientific-sounding terminology without testable mechanisms, controlled studies, or falsifiable predictions
c)
Doctors don't understand quantum physics well enough
d)
It might work but hasn't been tested yet
13.
Weather models can predict 3-5 days out but become unreliable beyond that. What does this reveal about scientific models?
a)
Weather models are useless and should be abandoned
b)
All models have limitations based on system complexity and available data; uncertainty doesn't invalidate useful predictions
c)
Scientists just need better computers
d)
Weather is completely random and unpredictable
14.
A study finds coffee drinkers live longer than non-drinkers. A news headline claims "Coffee Causes Longer Life." Critique this conclusion.
a)
Valid conclusion; the study proves causation
b)
Invalid; correlation doesn't prove causation. Confounding variables like lifestyle, genetics, or income may explain both coffee drinking and longevity
c)
Valid; coffee is known to be healthy
d)
Invalid; only experimental studies can find any patterns
15.
A company sells magnetic bracelets claiming they "realign your body's energy fields" to reduce pain. Design an experiment to test this claim scientifically. What is MOST critical?
a)
Survey bracelet users about their pain levels
b)
Conduct a double-blind, placebo-controlled study where neither participants nor researchers know who has real vs fake bracelets
c)
Measure the magnetic field strength of the bracelets
d)
Ask doctors whether they recommend the product
16.
Students test if fertilizer helps plants grow. Group A gets fertilizer + lots of water. Group B gets no fertilizer + little water. Identify the PRIMARY flaw in this experimental design.
a)
They need more groups to test
b)
Multiple variables changed simultaneously (fertilizer AND water); cannot determine which variable caused any observed difference
c)
They need more plants in each group
d)
They should test more types of fertilizer
17.
In the 1600s, geocentric (Earth-centered) and heliocentric (Sun-centered) models competed. What scientific evidence would BEST distinguish between them?
a)
Religious texts supporting geocentric model
b)
Observations of planetary retrograde motion are explained more simply by heliocentric model (Occam's Razor)
c)
Majority of scientists believed geocentric model
d)
Geocentric model is older and more established
18.
The scientific community initially rejected plate tectonics theory. Later, convergent evidence from geology, paleontology, and oceanography supported it. What does this reveal about scientific consensus?
a)
Scientists are stubborn and resist new ideas
b)
Scientific consensus forms gradually as evidence accumulates from multiple independent sources and methods
c)
One study is enough to establish consensus
d)
Consensus means every single scientist must agree
19.
Design an investigation to test whether room temperature affects battery life. What is MOST important to control?
a)
Use different battery brands to see which is best
b)
Keep all variables constant except temperature: use identical batteries, devices, usage patterns, and measure discharge time at different temps
c)
Test at only one temperature to ensure accuracy
d)
Survey battery manufacturers about their products
20.
Which quantity has both magnitude and direction?
a)
Vector
b)
Scalar
c)
Mass
d)
Energy
21.
Which is a scalar quantity?
a)
Velocity
b)
Displacement
c)
Acceleration
d)
Distance
22.
A person walks 6 km north, then 8 km east. What is the magnitude of displacement?
a)
14 km
b)
10 km
c)
2 km
d)
48 km
23.
The vertical component of a 50 N force at 30° above horizontal is:
a)
43.3 N
b)
25 N
c)
50 N
d)
86.6 N
24.
Two forces: 30 N east and 40 N north act on an object. Why can't you simply add 30 + 40 = 70 N?
a)
Math doesn't work that way for forces
b)
Perpendicular vectors must be added using the Pythagorean theorem, not arithmetic addition
c)
You can add them that way - it's correct
d)
Forces always cancel when perpendicular
25.
A GPS device shows you traveled 45 km in 30 minutes, but your displacement from start to finish is only 20 km. What does this indicate?
a)
The GPS is malfunctioning
b)
You drove along a curved or indirect path; distance traveled is greater than straight-line displacement
c)
Distance and displacement are the same thing
d)
You must have driven in a perfectly straight line
26.
Why is velocity (not speed) essential for autonomous vehicle navigation systems?
a)
Velocity is always a larger number than speed
b)
Velocity includes directional information needed to determine heading, plan routes, and coordinate with other vehicles
c)
Speed is impossible to measure in moving vehicles
d)
Velocity and speed are identical quantities
27.
A force of 100 N acts at 60° above horizontal pulling a sled. Why do engineers resolve this into horizontal and vertical components?
a)
It's unnecessary mathematical complication
b)
Only the horizontal component does work moving the sled forward; the vertical component affects normal force and friction
c)
Components are just for practice problems
d)
The original 100 N force doesn't physically exist
28.
Two equal forces act at 120° angle apart. How does their resultant compare to a single force with twice the magnitude?
a)
The resultant equals twice one force
b)
The resultant equals one force (vectors at 120° largely oppose each other)
c)
The resultant is zero
d)
The resultant is three times one force
29.
You need to add 10 vectors of various magnitudes and directions. What is the most efficient method?
a)
Draw all 10 vectors head-to-tail graphically and measure
b)
Resolve each vector into x and y components, sum all x-components, sum all y-components, then find resultant magnitude and direction
c)
Add all the magnitudes together arithmetically
d)
Impossible to add more than 2 vectors
30.
A rescue helicopter must drop supplies to a boat moving east at 15 m/s. The helicopter flies at 40 m/s and a 20 m/s wind blows from the west (toward east). At what velocity should the helicopter fly to match the boat's eastward velocity?
a)
Fly directly east at 40 m/s
b)
Fly west at 25 m/s so that wind (20 m/s east) + helicopter motion results in 15 m/s east net velocity... wait that's only 5 m/s
c)
Fly east at 15 m/s to match boat
d)
Impossible with these conditions
31.
A hiker walks 3 km east, then 4 km south, then 3 km west. What is the magnitude of total displacement?
a)
10 km
b)
4 km
c)
7 km
d)
5 km
32.
A boat must cross a 120 m wide river, heading perpendicular to the banks at 4 m/s. A current flows downstream at 3 m/s. Calculate: (a) time to cross, (b) how far downstream it lands, (c) actual distance traveled.
a)
(a) 30s, (b) 90m, (c) 150m
b)
(a) 40s, (b) 120m, (c) 169m
c)
(a) 30s, (b) 0m, (c) 120m
d)
(a) 15s, (b) 45m, (c) 75m
33.
Three forces act on a box at equilibrium: Force A = 50 N east, Force B = 30 N north. Determine the magnitude and direction of Force C.
a)
Cannot determine; insufficient information
b)
C must have components 50 N west and 30 N south (magnitude ≈ 58 N at angle southwest) to achieve zero net force
c)
C = 80 N in any direction
d)
C = 20 N directly south
34.
A plane flies 500 km at heading 30° north of east. Calculate: (a) eastward displacement, (b) northward displacement, (c) explain why knowing both components is essential for aviation.
a)
Cannot solve without airspeed
b)
(a) 433 km east, (b) 250 km north; both needed to determine actual position for navigation, fuel calculations, and landing approach vectors
c)
(a) 250 km, (b) 433 km; only one component matters
d)
(a) 500 km, (b) 0 km; heading determines everything
35.
Acceleration is defined as:
a)
Change in position
b)
Change in velocity
c)
Rate of change of position
d)
Rate of change of velocity
36.
The slope of a position-time graph represents:
a)
Acceleration
b)
Velocity
c)
Displacement
d)
Force
37.
A car travels 80 km north then 50 km south. What is the displacement?
a)
130 km
b)
30 km north
c)
30 km south
d)
80 km north
38.
An object accelerates from rest at 2.5 m/s² for 8 seconds. What is its final velocity?
a)
0.3 m/s
b)
10.5 m/s
c)
20 m/s
d)
16 m/s
39.
A ball is dropped from rest and falls for 3 seconds. How far does it fall? (g = 10 m/s² for simplicity)
a)
30 m
b)
45 m
c)
90 m
d)
15 m
40.
The area under a velocity-time graph represents:
a)
Acceleration
b)
Average velocity
c)
Displacement
d)
Speed
41.
A runner accelerates from rest to 8 m/s in 4 seconds. What is the acceleration?
a)
32 m/s²
b)
12 m/s²
c)
2 m/s²
d)
0.5 m/s²
42.
A position-time graph shows a curve with increasing slope. What does this indicate about the motion?
a)
Constant velocity
b)
Increasing velocity (acceleration)
c)
Decreasing velocity
d)
Object is at rest
43.
If a car's initial velocity doubles while braking acceleration stays constant, how does stopping distance change?
a)
Doubles
b)
Quadruples
c)
Stays the same
d)
Halves
44.
A student calculates that a ball thrown upward at 25 m/s stays in the air for 2.5 seconds. Identify the error. (g = 10 m/s²)
a)
Correct calculation
b)
Student forgot the ball must come back down; total time is 5 seconds (2.5s up + 2.5s down)
c)
Student used wrong value for g
d)
Balls thrown upward never return
45.
A velocity-time graph shows a horizontal line at v = 10 m/s. What is the object's acceleration?
a)
10 m/s²
b)
0 m/s²
c)
-10 m/s²
d)
Cannot be determined
46.
Compare two objects dropped simultaneously: Object A from 20m, Object B from 45m. Which hits ground first and why?
a)
A hits first; less distance to fall
b)
B hits first; higher initial potential energy
c)
They hit simultaneously; gravity accelerates both equally
d)
Cannot determine without knowing masses
47.
In projectile motion, at the highest point the vertical velocity is _____ and the vertical acceleration is _____.
a)
Zero; zero
b)
Zero; 9.8 m/s² downward
c)
Maximum; zero
d)
Maximum; 9.8 m/s² downward
48.
Position data: t=0s x=0m, t=1s x=5m, t=2s x=20m, t=3s x=45m. What type of motion?
a)
Constant velocity
b)
Constant acceleration
c)
Decreasing acceleration
d)
Constant position
49.
A car accelerates from rest at 3 m/s² for 4 seconds, then maintains constant velocity for 6 seconds, then brakes at -2 m/s² until stopped. Calculate the total distance traveled.
a)
24 m
b)
120 m
c)
144 m
d)
96 m
50.
Two balls are thrown vertically upward: Ball A at 20 m/s, Ball B at 30 m/s. Compare their maximum heights using energy principles.
a)
A and B reach the same height
b)
B reaches 2.25 times higher than A because height is proportional to v²
c)
B reaches 1.5 times higher because it's 1.5× faster
d)
Cannot compare without knowing masses
51.
A ball is thrown horizontally at 15 m/s from a 45m tall cliff. Calculate: (a) time to hit ground, (b) horizontal distance traveled, (c) final velocity magnitude. (g = 10 m/s²)
a)
(a) 4.5s, (b) 67.5m, (c) 15 m/s
b)
(a) 3s, (b) 45m, (c) √(15²+30²) ≈ 34 m/s
c)
(a) 3s, (b) 30m, (c) 30 m/s
d)
(a) 1.5s, (b) 22.5m, (c) 25 m/s
52.
An engineer designs a runway for planes landing at 80 m/s. Safety requires deceleration ≤ 3 m/s² for passenger comfort. Calculate minimum safe runway length.
a)
267 m
b)
1067 m
c)
240 m
d)
2400 m
53.
A police car starts from rest and accelerates at 4 m/s² chasing a suspect already 100m ahead traveling at constant 20 m/s. When does the police car catch the suspect?
a)
5 seconds
b)
10 seconds
c)
20 seconds
d)
Never catches up
54.
Design an experiment to measure human reaction time using only a dropped ruler that a person catches. Explain the physics principle and how to calculate reaction time.
a)
Just time how long until they say "now"
b)
Drop ruler; measure distance it falls before catch; use d = ½gt² to calculate time (reaction time)
c)
Use a stopwatch to time the catch directly
d)
Reaction time cannot be measured with a ruler
55.
Newton's First Law (Law of Inertia) states that:
a)
F = ma
b)
Objects at rest stay at rest and objects in motion stay in motion unless acted upon by a net force
c)
For every action there is an equal and opposite reaction
d)
Heavier objects fall faster than light objects
56.
The SI unit for force is:
a)
Kilogram (kg)
b)
Newton (N)
c)
Joule (J)
d)
Watt (W)
57.
Weight is defined as:
a)
The same thing as mass
b)
The gravitational force acting on an object (W = mg)
c)
Always measured in kilograms
d)
Constant everywhere in the universe
58.
A 5 kg object experiences a net force of 20 N. What is its acceleration?
a)
4 m/s²
b)
15 m/s²
c)
25 m/s²
d)
100 m/s²
59.
What is the weight of a 70 kg person on Earth? (g = 9.8 m/s²)
a)
70 N
b)
7.14 N
c)
686 N
d)
7000 N
60.
You push a wall with 50 N of force. According to Newton's Third Law, the wall pushes back with:
a)
Less than 50 N
b)
Exactly 50 N
c)
More than 50 N
d)
Zero force
61.
A 20 kg box on a surface has μs = 0.4. What is the maximum static friction force? (g = 10 m/s²)
a)
8 N
b)
50 N
c)
80 N
d)
200 N
62.
What net force is required to accelerate a 10 kg object at 3 m/s²?
a)
3.33 N
b)
13 N
c)
30 N
d)
7 N
63.
If net force on an object doubles while mass stays constant, the acceleration:
a)
Stays the same
b)
Doubles
c)
Halves
d)
Quadruples
64.
The normal force acts:
a)
Parallel to the contact surface
b)
Perpendicular to the contact surface
c)
At 45° to the surface
d)
Downward toward Earth's center
65.
Friction always acts:
a)
Perpendicular to the direction of motion
b)
Opposite to the direction of motion or intended motion
c)
In the same direction as motion
d)
Vertically upward
66.
A book rests on a table. The book's weight (downward) and the normal force (upward) are equal and opposite. Are these an action-reaction pair from Newton's Third Law?
a)
Yes - they are equal and opposite forces
b)
No - action-reaction pairs must act on different objects; these both act on the book
c)
Yes - they balance to create equilibrium
d)
No - the normal force is always larger
67.
Why is it easier to push a box across a smooth floor than a rough carpet?
a)
The box has less mass on smooth floors
b)
Smooth floors have a lower coefficient of friction, resulting in less friction force
c)
The normal force is less on smooth floors
d)
Gravity is weaker near smooth surfaces
68.
Equal forces act on two objects for the same time. Object A (mass 2 kg) reaches 10 m/s. What final velocity does Object B (mass 5 kg) reach?
a)
10 m/s - same force gives same velocity
b)
4 m/s - impulse Ft = mΔv, so for same Ft, velocity change inversely proportional to mass
c)
25 m/s - heavier objects go faster
d)
2 m/s
69.
A student pushes a 20 kg box with 100 N but it doesn't move. Student says "F=ma is wrong because a = 100/20 = 5 m/s² but box is stationary." Identify the flaw in reasoning.
a)
Newton's Second Law doesn't apply to boxes
b)
Static friction provides an opposing force; NET force is zero, so a = 0. F = ma uses net force, not individual forces
c)
The calculation is correct; Newton's Second Law is wrong
d)
The box is too heavy for physics laws to apply
70.
An astronaut has mass 80 kg on Earth. What is their mass on the Moon where g = 1.6 m/s²?
a)
13.3 kg
b)
80 kg
c)
128 kg
d)
48 kg
71.
Two identical cars travel at the same speed. Car A brakes on dry pavement (μ = 0.8), Car B brakes on ice (μ = 0.1). Compare their stopping distances.
a)
Equal stopping distances
b)
Car B takes 8 times longer to stop
c)
Car B takes twice as long to stop
d)
Ice has no effect on stopping distance
72.
A horse pulls a cart forward. The cart pulls the horse backward with equal force (Newton's 3rd Law). If forces are equal, how can the cart move forward?
a)
The forces don't actually cancel out
b)
Action-reaction pairs act on different objects; analyze net force on each object separately (horse experiences ground friction)
c)
Newton's Third Law is wrong in this case
d)
The horse is stronger than the cart
73.
A rocket accelerates in outer space where there is no air. How does Newton's Third Law explain this motion?
a)
The rocket pushes against space itself
b)
The rocket expels exhaust gases backward (action); gases push rocket forward (reaction)
c)
Rockets don't actually work in space - this is a movie myth
d)
Gravity from nearby planets pulls the rocket
74.
Why do car manufacturers design crumple zones that deform in crashes rather than making cars extremely rigid?
a)
Rigid cars are too expensive to manufacture
b)
Crumple zones increase collision time, reducing force on passengers (F = Δp/Δt)
c)
Crumple zones look better aesthetically
d)
Rigid cars are too heavy
75.
A 25 kg box on a truck bed has μs = 0.4. The truck accelerates forward. What is the maximum truck acceleration before the box slides backward relative to the truck bed?
a)
10 m/s²
b)
4 m/s²
c)
0.4 m/s²
d)
2.5 m/s²
76.
You stand on a scale in an elevator accelerating upward at 2 m/s². Your mass is 60 kg. What does the scale read? (g = 10 m/s²)
a)
600 N
b)
720 N
c)
480 N
d)
120 N
77.
A 1000 kg car must stop from 25 m/s in 50 m. Calculate required braking force. Is μ = 0.65 on dry pavement sufficient?
a)
Need 12,500 N; μ provides 6500 N - insufficient
b)
Need 6250 N; μ provides 6500 N - adequate (barely)
c)
Need 500 N; easily sufficient
d)
Need 25,000 N; insufficient
78.
A 60 kg person jumps from a 1.8 m height, landing with bent knees (impact time 0.3s) vs straight legs (0.1s). Compare the impact forces. (g = 10 m/s²)
a)
Same force in both cases
b)
Bent knees: ~1260 N; Straight legs: ~3780 N. Longer impact time significantly reduces force
c)
Bent knees experience more force
d)
Impact time doesn't affect force
79.
Three blocks (2 kg, 3 kg, 5 kg) sit in contact on a frictionless surface. You push the first block with 50 N. What force does the middle block exert on the last block?
a)
50 N - force transmits unchanged
b)
25 N - system accelerates at a = 50/10 = 5 m/s²; last block needs F = 5×5 = 25 N
c)
10 N
d)
5 N
80.
A 50 kg box sits on a 30° incline with μs = 0.25. Calculate: (a) component of weight parallel to incline, (b) maximum static friction, (c) Does the box slide? (g = 10 m/s²)
a)
(a) 250 N, (b) 125 N, (c) Yes, slides
b)
(a) 250 N, (b) 108 N, (c) Yes, slides (250 N > 108 N)
c)
(a) 433 N, (b) 108 N, (c) Yes
d)
(a) 250 N, (b) 250 N, (c) No, doesn't slide
81.
Design a demonstration using two bathroom scales to show Newton's Third Law. Describe setup and expected readings.
a)
Cannot demonstrate with bathroom scales
b)
Place one scale on ground, stand on it while pushing another scale against a wall. Both scales show equal force readings
c)
Use only one scale - stand and jump
d)
Stack both scales and stand on top
82.
A 10 kg block on frictionless ice is connected by a rope over a pulley to a 6 kg hanging mass. The rope passes over a frictionless pulley. Calculate system acceleration. (g = 10 m/s²)
a)
a = 3.75 m/s²
b)
a = 6 m/s²
c)
a = 10 m/s²
d)
System doesn't move
83.
In a car crash, why do airbags reduce injury more effectively than hitting a solid dashboard?
a)
Airbags are softer and more comfortable
b)
Airbags increase collision time, reducing force (F = Δp/Δt) for the same momentum change
c)
Airbags absorb all the momentum
d)
Airbags prevent any force from acting
84.
Two masses (m₁ = 2 kg, m₂ = 3 kg) hang over a massless, frictionless pulley. Calculate acceleration when released. (g = 10 m/s²)
a)
a = 2 m/s²
b)
a = 5 m/s²
c)
a = 10 m/s²
d)
a = 6 m/s²
85.
Anti-lock brakes (ABS) prevent wheels from locking during emergency braking. Using physics, explain why this reduces stopping distance.
a)
ABS applies more total braking force
b)
Locked wheels slide (kinetic friction μk); ABS maintains rolling (static friction μs > μk), providing better traction
c)
ABS reduces the mass of the car
d)
ABS makes the road smoother
86.
Energy is measured in:
a)
Newtons
b)
Joules
c)
Watts
d)
Pascals
87.
Power is defined as:
a)
The amount of work done
b)
The rate at which work is done or energy is transferred
c)
The force applied to an object
d)
The energy stored in an object
88.
The SI unit for power is:
a)
Joule
b)
Newton
c)
Watt
d)
Horsepower
89.
What is the kinetic energy of a 1200 kg car traveling at 20 m/s? (KE = ½mv²)
a)
12,000 J
b)
24,000 J
c)
240,000 J
d)
480,000 J
90.
What is the gravitational potential energy of a 2 kg book on a 2.5 m high shelf? (PE = mgh, g = 10 m/s²)
a)
5 J
b)
20 J
c)
50 J
d)
25 J
91.
How much work is done when a 200 N force moves an object 10 m in the direction of the force? (W = Fd)
a)
20 J
b)
210 J
c)
2,000 J
d)
20,000 J
92.
If 600 J of work is done in 15 seconds, what is the power? (P = W/t)
a)
9,000 W
b)
40 W
c)
615 W
d)
585 W
93.
A 0.5 kg ball is dropped from a height of 20 m. What is its speed just before hitting the ground? (g = 10 m/s²)
a)
10 m/s
b)
14 m/s
c)
20 m/s
d)
200 m/s
94.
If an object's velocity doubles, its kinetic energy:
a)
Doubles
b)
Quadruples
c)
Halves
d)
Stays the same
95.
The Law of Conservation of Energy states:
a)
Energy can be created but not destroyed
b)
Energy cannot be created or destroyed, only transformed from one form to another
c)
Energy always increases over time
d)
Energy eventually runs out
96.
A pendulum swings back and forth. At what point is kinetic energy maximum and potential energy minimum?
a)
At the highest point of the swing
b)
At the lowest point of the swing
c)
Halfway up on either side
d)
KE and PE are always equal
97.
A ball dropped from height h bounces back to height h/2. Where did the "lost" energy go?
a)
Energy disappeared - conservation doesn't apply here
b)
Energy transformed to sound, heat, and deformation of ball and floor
c)
The ball gained mass so energy decreased
d)
Energy was absorbed into the ground permanently
98.
A student claims: "A heavy truck and a small car traveling at the same speed have equal kinetic energy." Evaluate this claim.
a)
True - same speed means equal kinetic energy
b)
False - KE = ½mv², so at equal speeds the more massive truck has proportionally more KE
c)
True - kinetic energy only depends on speed, not mass
d)
Cannot compare vehicles of different types
99.
You do 500 J of work pushing a box 10 m across a floor, but the box's kinetic energy only increases by 200 J. What happened to the other 300 J?
a)
The energy disappeared
b)
300 J was converted to thermal energy (heat) by friction between box and floor
c)
There must be a calculation error
d)
The energy is stored in the box
100.
"If you double your car's speed, your braking distance doubles." Evaluate this claim using energy principles.
a)
Correct - linear relationship between speed and distance
b)
Incorrect - KE ∝ v², so doubling speed quadruples the energy that must be dissipated, thus quadrupling braking distance
c)
Correct - speed and distance are directly proportional
d)
Braking distance is independent of speed
101.
In a hydroelectric dam, trace the energy transformations from rainwater in mountains to electricity in your home.
a)
Only one transformation occurs: water to electricity
b)
Gravitational PE (elevated water) → Kinetic energy (flowing water) → Rotational KE (turbine) → Electrical energy; losses at each stage to heat/sound
c)
Chemical energy → electrical energy
d)
Water creates energy from nothing
102.
A roller coaster starts from rest at height h. Designers want maximum speed at the bottom. Does the shape of the track (steep drop vs gradual slope) affect final speed? Explain.
a)
Steepest drop gives fastest speed
b)
Track shape doesn't matter for final speed; energy conservation means PE = KE, final speed depends only on height difference, not path
c)
Gradual slope gives fastest speed
d)
Need more information about friction
103.
Person A climbs stairs in 10 seconds. Person B climbs the same stairs in 20 seconds. Same mass. Compare their power outputs.
a)
Equal power - same work done
b)
A has twice the power of B - same work in half the time (P = W/t)
c)
B has more power - took longer
d)
Cannot compare without knowing exact masses
104.
Pendulum swings in air vs in a vacuum. How does total mechanical energy change over time in each case?
a)
Both conserve energy perfectly forever
b)
Vacuum conserves mechanical energy; air causes decrease as mechanical energy transforms to thermal via air resistance (non-conservative force)
c)
Air conserves energy better than vacuum
d)
Both increase in energy over time
105.
A 5 kg pendulum is released from 2 m height, swings down and collides inelastically with a 2 kg block at rest. How high do they rise together after collision? (g = 10 m/s²)
a)
2 m - same height
b)
1.02 m
c)
0.5 m
d)
4 m
106.
A roller coaster car of mass 500 kg starts from rest at the top of a 50 m hill. If 30% of its initial potential energy is lost to friction, what is its speed at the bottom? (g = 10 m/s²)
a)
50 m/s
b)
26 m/s
c)
31 m/s
d)
35 m/s
107.
A machine lifts a 200 kg object by 5 m in 20 seconds. Input power is 600 W. Calculate the efficiency of the machine. (g = 10 m/s²)
a)
100% efficient
b)
83% efficient (Useful work = mgh = 10,000 J; Input energy = Pt = 12,000 J; eff = 10,000/12,000)
c)
50% efficient
d)
200% efficient - violates conservation
108.
A 10 kg block compresses a spring (k = 500 N/m) by 0.4 m, then is released to slide up a frictionless 30° incline. How far up the incline does it travel before stopping? (g = 10 m/s²)
a)
0.4 m
b)
0.8 m
c)
1.6 m
d)
0.2 m
109.
A 60 kg skydiver reaches terminal velocity of 50 m/s. Calculate the power dissipated by air resistance at terminal velocity. (g = 10 m/s²)
a)
600 W
b)
30,000 W
c)
3,000 W
d)
0 W - no acceleration
110.
Design a simple mechanical energy storage system using a 100 kg mass. If lifted 10 m, how much energy is stored? How long could it power a 100 W light bulb? (g = 10 m/s²)
a)
1,000 J stored; 10 seconds
b)
10,000 J stored; 100 seconds
c)
100 J stored; 1 second
d)
Cannot store energy by lifting mass
111.
A car moving at 20 m/s brakes to 10 m/s. What fraction of its kinetic energy was dissipated?
a)
1/2 (half)
b)
1/4 (one quarter)
c)
3/4 (three quarters)
d)
1/3 (one third)
112.
High jumper (mass 70 kg) runs horizontally at 8 m/s then converts this to vertical jump. Assuming 100% efficient conversion, what maximum height is theoretically possible? (g = 10 m/s²)
a)
8 m
b)
3.2 m
c)
0.8 m
d)
64 m
113.
The acceleration due to gravity near Earth's surface is approximately:
a)
9.8 km/s²
b)
9.8 m/s²
c)
9.8 cm/s²
d)
9.8 m/s
114.
An object has mass 60 kg on Earth. What is its mass on the Moon where g = 1.6 m/s²?
a)
10 kg
b)
60 kg
c)
96 kg
d)
37.5 kg
115.
If both masses in a gravitational system double while distance stays constant, the gravitational force:
a)
Stays the same
b)
Doubles
c)
Quadruples
d)
Becomes eight times larger
116.
Astronauts aboard the ISS (orbiting 400 km up where Earth's gravity is ~90% of surface value) appear weightless. Explain this apparent paradox.
a)
Gravity doesn't exist in space
b)
Weightlessness is continuous free fall; astronaut and ISS fall together toward Earth, creating apparent weightlessness
c)
Moon's gravity cancels Earth's gravity
d)
They are too far from Earth for gravity
117.
If Earth's radius doubled but mass stayed the same, your weight would:
a)
Double
b)
Quadruple
c)
Become one-quarter as much
d)
Stay the same
118.
Newton's Law of Universal Gravitation states force between masses is proportional to the product of masses and inversely proportional to distance squared. If distance triples, force becomes:
a)
Three times weaker
b)
Nine times weaker
c)
One-third as strong
d)
One-ninth as strong
119.
Two planets: Planet A has mass M and radius R. Planet B has mass 4M and radius 2R. Compare the gravitational field strength (g) at their surfaces.
a)
gB = 4gA
b)
gB = gA (same surface gravity)
c)
gB = 2gA
d)
gB = gA/2
120.
A satellite orbits Earth at radius 2R (where R = Earth radius). Compare its orbital speed to a satellite at radius R. Use: orbital speed v ∝ √(1/r)
a)
Same speed at both radii
b)
Speed at 2R is 1/√2 times speed at R (about 0.71×)
c)
Speed at 2R is double
d)
Speed at 2R is half
121.
A cyclist travels 6 km north, then 8 km west. What is the magnitude of the total displacement?
a)
14 km
b)
10 km
c)
2 km
d)
48 km
122.
An object starts from rest and accelerates at 3 m/s² for 5 seconds. What is its final velocity?
a)
5 m/s
b)
3 m/s
c)
15 m/s
d)
8 m/s
123.
A car moves 100 m east, then 75 m north. What is the straight-line distance from its starting point?
a)
75 m
b)
100 m
c)
125 m
d)
175 m
124.
Which of the following is a key characteristic of a scientific hypothesis?
a)
It must be proven true before experimentation
b)
It is accepted without evidence
c)
It can be tested and potentially falsified through experiments
d)
It is based on unchangeable beliefs
125.
A student measures the acceleration due to gravity as 9.6 m/s², while the accepted value is 9.8 m/s². What should the student do?
a)
Ignore the difference; all measurements are perfect
b)
Repeat the experiment and check for errors or uncertainties
c)
Change the result to match the accepted value
d)
Assume the accepted value is incorrect
126.
Which statement best explains why scientific experiments are repeated by different researchers?
a)
To ensure results are reproducible and not due to chance or bias
b)
To waste resources
c)
To prove the original scientist wrong
d)
To get different answers each time
127.
A new scientific theory is proposed but lacks supporting evidence from independent experiments. What is the most appropriate scientific response?
a)
Wait for multiple lines of evidence and independent verification before accepting the theory
b)
Reject the theory because it's new
c)
Assume the theory is false until proven otherwise
d)
Accept the theory immediately
128.
A nutrition study finds that people who eat more vegetables tend to have lower rates of heart disease. What is the best interpretation of this result?
a)
The study proves causation
b)
Vegetables are unhealthy
c)
There is a correlation, but other factors like exercise or genetics could be involved
d)
Eating vegetables directly prevents heart disease
129.
A company claims their wristband improves athletic performance but provides only testimonials as evidence. What is the main scientific criticism of this claim?
a)
Athletes always tell the truth
b)
The company is trustworthy
c)
If many people believe it, it must be true
d)
Testimonials are not reliable evidence; controlled, repeatable experiments are needed
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