8th Grade Science Released Tests

The location on the track where the train has the greatest potential energy is —
1. 1
2. 2
3. 3
4. 4
The area that shows the amplitude of the wave is —
1. 1
2. 2
3. 3
4. 4
During a fireworks show, a family sees the spray of sparkles from an exploding firework high in the sky and, a moment later, hears the pop. Which of these best explains why the pop and spray do not seem to occur at the same time?
1. Light and sound travel through air.
2. Sound travels through a vacuum.
3. Sound travels slower than light.
4. Light and sound travel at the same speed.
A mixture of iron filings and sulfur can easily be separated by —
1. placing the mixture in water
2. performing a chemical reaction
3. heating the mixture
4. using a magnet
According to the data in the table, which sample of matter is most likely a metal?
1. 1
2. 2
3. 3
4. 4
At which point is the magnetic field the strongest?
1. Point 1
2. Point 2
3. Point 3
4. Point 4
Convection is the result of —
1. currents caused by the motion of heated molecules
2. increases in the density of solids
3. colder portions of liquids rising
4. the lack of heat transfer
Because burning fossil fuels creates much pollution, alternatives are being investigated. What might limit the use of wind as a major energy source?
1. The strength of the wind varies.
2. Wind machines have huge blades to capture the wind.
3. Turbines and generators in the wind machines create electricity.
4. Wind power does not create pollution.
Electric bills are calculated based on the amount of energy consumed. The consumption is measured in units of —
1. newton meters
2. millijoule seconds
3. megavolt minutes
4. kilowatt hours
A group of people were concerned about a new coal-burning power plant that might be built in their neighborhood. What is probably their main concern?
1. Burning coal produces more heat than burning wood.
2. The heat from burning coal can drive generators that produce electricity.
3. Burning coal produces sulfur dioxide which contributes to acid rain.
4. There is more coal in the earth than there is oil and gas.
Objects with like charges repel and unlike charges attract. The girl’s hair and the comb have —
1. unlike charges
2. like charges
3. neutral charges
4. no charges
When plants perform photosynthesis, they use sunlight to produce food. This is an example of light energy being converted to —
1. heat energy
2. electrical energy
3. mechanical energy
4. chemical energy
Which of the following is an example of potential energy?
1. A glass jar sitting on a shelf
2. A flag waving in the wind
3. A ball rolling along a sidewalk
4. A battery powering a radio
Which of the following could best be used to demonstrate energy being transformed from electricity to heat?
1. A magnifying glass
2. A triple beam balance
3. A toaster
4. A gas oven
The distance between one point on a compression and the corresponding point on the next compression in a sound wave is called a —
1. wavelength
2. rarefaction
3. crest
4. trough
The illustration shows a wave. The wave’s wavelength is the distance between points —
1. 1 and 2
2. 1 and 4
3. 2 and 3
4. 2 and 4
Which diagram best shows the reflection of light?
Fossil fuels such as gas, oil, and coal have what kind of energy?
1. Mechanical energy
2. Chemical energy
3. Electrical energy
4. Nuclear energy
Which of the following is a true statement about the magnetic field between two magnets?
1. The south pole of one magnet is attracted to the south pole of the other magnet.
2. The south pole of one magnet is attracted to the north pole of the other magnet.
3. The north pole of one magnet is attracted to the north pole of the other magnet.
4. The south pole of one magnet is attracted to both poles of the other magnet.
Which of these has the greatest number of different simple machines?
A car manufacturer reduces the mass of a car by 250 kg. If the new design is otherwise identical to the old design, how will the new car compare to the old car?
1. It will have a greater gravitational attraction to the road.
2. It will require more fuel to operate.
3. It will need less force to move.
4. It will release more gas emissions.
Energy from the Sun is distributed around Earth by —
1. subduction and rift zones
2. radiation and convection
3. tectonic plates
4. solar flares

8th Grade Science Released Tests - Energy Review 2