Motion and Force Review

SPEED

• Speed is the measure how quickly distance changes with time..

• Average speed can be found by taking the total distance dividing by total time of travel

• Units for speed include mph with SI unit being m/s.

Multiple Choice

Toby can run 15 meters in 5 seconds. What is his speed?

• 5 m/s

• 2 m/s

• 3 m/s

• 75 m/s

Multiple Choice

What is the formula to calculate speed?

• S = t / d

• S = d * t

• S = t * d

• S = d / t

Multiple Choice

At what speed would a car have to move in order to travel 20 kilometers in 2 hours.

• 5 km/hr

• 10 km/hr

• 20 km/hr

• 40 km/hr

VELOCITY

• Velocity of an object is its speed combined with the direction of the motion

• Just add the direction to the speed and you have velocity

• An example of velocity would be 70m/s south

Multiple Select

Check the correct examples of velocity

• 6km/h

• 4 km/h north

• 70mph

• 70mph east

• 25 feet per minute up

Multiple Choice

The geese fly 23 mph to the south when they migrate for the winter.

• speed

• velocity

• acceleration

Multiple Choice

A helicopter flies west 200 miles in 2 hours. What is its velocity?

• 99 mph

• 100 mph south

• 400 mph south

• 297 mph south

ACCELERATION

• A Change in motion caused by an unbalanced force acting on an object; includes increasing speed, decreasing speed or change in an objects motion.

Multiple Choice

You are riding your bike at 9 km/h. Ten minutes later, your speed is 6 km/h.

• Acceleration occurred because speed increased.
• Acceleration occurred because speed decreased.
• Acceleration occurred because you changed directions.

Speed Graph

Speed graphs always have distance on the Y-axis and time on the X-axis. Straight, diagonal lines show constant speed. Flat, horizontal lines show the object is standing still, at rest.

Multiple Choice

How far did the swimmers swim?

• 100 m

• 0 m

• 50 m

• 110 m

Multiple Choice

What is the speed of this object 20 minutes?

• 2 km/m

• 20 km/m

• 0.5 km/m

• 10 km/m

Multiple Choice

How fast is the object traveling between 2.5 and 3.5 seconds?

• 3 mph

• 6 mph

• The object is at rest.

• 4 mph

Multiple Choice

Describe the speed of the object from 4-6 seconds using the distance vs. time graph.

• Increasing speed
• Decreasing speed
• Not moving
• Constant speed

Multiple Choice

What is happening at segment C

• no motion/object at rest

• constant speed

• acceleration

Multiple Choice

What is happening at segment A?

• no motion/object at rest

• constant speed

• deceleration

Multiple Choice

Determine the motion of the car.

• at rest 
• moving at constant speed
• speeding up
• slowing down

Multiple Choice

What will cause an object to move and accelerate?

• Applied forces

• Balanced forces

• Unbalanced forces

Multiple Select

Newton's 2nd Law says the acceleration of an object depends on its _______ and ______. (Choose two answers)

• force

• weight

• gravity

• mass

Multiple Choice

Your car has a mass of 2500 kg and a force of 5000 N. What is its acceleration?

F=ma $$a=\frac{\text{F}}{m}$$ $$m=\frac{\text{}F}{\text{a}}$$

• 20 m/s²

• 2 m/s²

• 0.5 m/s²

• 120 N

Multiple Choice

A net force of 250 N is applied to an object that accelerates at a rate of 5 m/sec². What is the mass of the object?

f=ma $$m=\frac{F}{a}$$ $$a=\frac{F}{m}$$

• 50 kg

• 245 kg

• 0.02 kg

• 1250 kg

Multiple Choice

What is the net force and the direction of movement?

• 50 Newtons, Left
• 50 Newtons, Right
• 500 Newtons, RIght
• 450 Newtons, LEft

Multiple Choice

This type of force resists motion between two surfaces that are pressed together

• mass

• gravity
• friction
• a push

Multiple Choice

F= mass * acceleration

A 20 kg bike accelerates at 10 m/s². what is the force acting upon it?

• 25 Newtons

• 20 Newtons

• 200 Newtons

• 10 Newtons

Multiple Choice

What is the difference between mass and weight?

• mass is how much matter is in an object, and weight is the gravitational pull on that object
• mass and weight are the same
• weight affects how much mass is in an object
• weight is determined by how many atoms make up an object

Multiple Choice

What does the strength of gravity between two objects depend upon?

• Inertia & mass

• Mass & weight
• Gravity & inertia
• Mass & distance

Multiple Select

check TWO that apply to Newton's 3rd law

• a girl pushes a sled and the sled accelerates

• a rocket takes off because the force from the engines pushes on the ground

• a balloon flies off when the opening is released

• gravity causes a ball to fall

Multiple Choice

A baseball player hits a ball with 400 N of force. How much force does the ball exert on the bat?

• 300

• 400

• 500

• Not enough info to tell