Grade 8 Physics Exam Practice

Multiple Choice

Look at the picture. Which type of plastic that will float in engine oil?

• cellulose acetate
• polyethylene
• polyvinyl chloride
• polystyrene

Multiple Select

Look at the picture. Which type of plastic that will sink in both water and engine oil?

• cellulose acetate
• polyethylene
• polyvinyl chloride
• polystyrene

Multiple Choice

Jack has a rock. The rock has a mass of 14g and a volume of 2cm³. What is the density of the rock?

• 7 mL
• 7 g/cm³
• 28 g/cm³
• 1/7 g/cm³

Multiple Choice

What units are used to measure Density?

• cm³/g
• g
• g/cm³
• cm³

Multiple Select

Sofia has two cups of coffee. The volume of the coffee in both cups is the same. One cup of coffee is at 55°C. The other cup is at 30°C. Which statement is true? (choose 2

• The temperature of the coffee in each cup is different

• The temperature of the coffee in each cup is the same

• The heat of the coffee in each cup is different

• The heat of the coffee in each cup is the same

Multiple Choice

Which statement is true about 15g of liquid at 20°C being cooled to 10°C with no change in mass?

• The temperature of the liquid is constant

• The heat of the liquid is constant

• The temperature of the liquid is decreasing as the mass decreases

• Both the heat and temperature of the liquid is decreasing as the temperature decreases

Multiple Choice

Which statement is true about 320g of liquid propanol at 50°C decreasing in mass to 220g at 50°C?

• The temperature of the liquid is constant, but the heat is decreasing

• The heat of the liquid is constant with no change in mass

• The heat of the liquid is decreasing as the mass decreases

• Both the heat and temperature of the liquid is decreasing as the temperature decreases

Multiple Choice

Which is the best surface for reflecting heat radiation?

• Shiny white

• Dull white

• Shiny black

• Dull black

Multiple Choice

The main reason for silvering in a vacuum flask is to ............................................................................

• Prevent heat transfer via convection

• Reduce heat transfer via radiation

• Prevent heat transfer via insulation

• Reduce heat transfer via conduction

Multiple Choice

The main reason for stopper in a vacuum flask is to ............................................................................

• Prevent heat transfer via radiation

• Reduce heat transfer via conduction

• Prevent heat transfer via insulation

• Reduce heat transfer via convection

Multiple Choice

In order to calibrate a degrees Celcius thermometer, the lowest fixed point can be found by placing the thermometer in ….

• pure boiling oil

• pure boiling water

• pure water

• pure melting ice

Multiple Choice

What  is the formula to calculate heat energy required to raise the temperature of any substance?

• Q=mc∆t
• Q=mc
• Q= ½mv
• m=QC

Multiple Choice

What does "ΔT" stand for?  

• A change in time
• A change in temperature in degrees C
• A change in mass
• A change in temperature in degrees F

Multiple Choice

Specific heat of water is  4.18 J/g°C. Specific heat of wood is 1.760 J/g°C What material needs more heat energy to raise the temperature?

• Water
• Wood
• Both are same

Multiple Choice

20 g of water. specific heat of water is 4200 J kg^-1°C^-1. temperature changes from 25° C to 20° C, how much heat energy (Q) moves from the water to the surroundings?

• 418 J

• 430 J

• 420 J

• 42000 J

Multiple Choice

When a sound is louder what measurement gets bigger?

• Frequency 
• Amplitude 
• Wavelength 
• Crest

Multiple Choice

If distance C on the diagram increased, what would happen to the pitch? 

• The pitch would be louder. 
• The pitch would be softer. 
• The pitch would be higher. 
• The pitch would be lower. 

Multiple Choice

A reflected sound wave

• frequency
• pitch
• echo
• rarefaction

Multiple Choice

Sonar and echolocation use ----- to detect objects under water.

• Refraction

• Reflection

Multiple Choice

Which wavelength would have the highest pitch like a flute or whistle?

• Upper wave diagram

• Lower wave diagram

Multiple Choice

Which device measures sound waves?

• Oscilloscope
• Stethoscope 
• Radio
• I don't know

Multiple Choice

What happens when the pair of waveforms interacts?

• The waveforms cancel each other out completely without any effect.
• The waveforms create a new waveform that is always flat.
• The waveforms interact which makes the sound reinforce

• The waveforms only interact if they are of different frequencies.

Multiple Choice

What happens when the pair of waveforms interacts?

• The waveforms cancel each other out completely without any effect.
• The waveforms create a new waveform that is always flat.
• The waveforms interact which makes the sound reinforce

• The waveforms only interact if they are of different frequencies.

Multiple Choice

a large, bowl-shaped cavity on the surface of the moon is called a...

• Maria

• Ray

• Phase

• Crater

Multiple Choice

Which is currently the most popular theory about the moon's formation?

• The Capture Theory

• The Accretion Theory

• The Fission Scenario

• The Giant Impact Theory

Multiple Choice

What did the analysis of samples from the Apollo missions suggest about the Earth and Moon?

• They are completely different

• They have similar composition

• They are made of different materials

• They have no similarities

Multiple Choice

What is the giant-impact theory of Moon formation based on?

• Collision between Earth and Mars

• Capture of a wandering body by Earth

• Creation of the Moon along with Earth

• Collision between Earth and Theia

Multiple Choice

Why are craters on the moon so well-preserved?

• No atmosphere = no precipitation for erosion
• The rocks on the moon are more solid
• The rocks on the moon absorb more impact

Multiple Choice

Which evidence that contradicts the Moon formation collision theory?

• The Moon has a different density than Earth.
• Surface of the Moon shows that it was once molten

• The Moon have iron core similar to Earth

• Venus has no moon

Multiple Choice

Which of the following is not a reason why Moon rocks collected support the collision theory?

• Moon rocks contains less iron than Earth

• Moon rocks has similar composition to the Earth

• Moon rocks have more density than the Earth rocks

• Moon rocks have very similar chemical content to Earth

Multiple Choice

What is stellar nursery?

• A stellar nursery is a planet formation zone.
• A stellar nursery is a region in space where new stars are formed.
• A stellar nursery is a black hole.
• A stellar nursery is a type of telescope.

Multiple Choice

What are nebulae?

• groups of exploding stars

• clouds of gas and dust in space

• a collection of stars

• groups of stars forming a pattern

Multiple Choice

Gravity pulls gases and dust particles in space toward one another, squeezing them into a smaller and smaller space. The temperature at the center rises high enough for nuclear fusion of hydrogen to begin.
What stage in a stars life cycle is this describing? 

• The birth of a star
• The death of a star
• Black Hole
• Stellar Nebula