Speed and Energy
Use evidence to explain the relationship between an object's speed and its energy.
Evidence such as a faster car or a fast ball moving another ball shows that faster-moving objects have more energy.
Name one observation that could be evidence that energy was transferred to an object.
The object moves, lights up or glows, makes a sound, or gets warmer.
True or False: There is no energy in empty space.
False
A moving ball hits a ball that is not moving. What might happen to the ball that was still?
It may start moving because energy is transferred to it during the collision.
A drum is hit harder and makes a louder sound. What is the evidence that energy changed?
The sound is louder, showing that more energy was transferred to the drum's vibrations and sound.
Which has more energy: a slowly rolling ball or the same ball rolling quickly?
The quickly rolling ball has more energy.
A flashlight shines on a wall. What kind of energy is transferred to the wall?
Light energy.
When the wound-up rubber band is released, what makes the racer move?
The stored energy transfers to the axle and wheels, making the car move forward.
Name two things you might observe when objects collide.
An object may bounce, change direction, move, break, or make a sound.
You clap softly, then clap loudly. What observation can you make about energy transfer?
The louder clap is evidence of more energy being transferred into sound.
A toy car rolls faster after you give it more energy. What evidence shows its motion changed?
It moves faster; it may also travel farther in the same amount of time.
You hear a dog bark from across the yard. What kind of energy reached your ears?
Sound energy.
If you wind the rubber band more, what do you predict will happen to the racer?
It will likely travel faster or farther because more stored energy is transferred to it.
After a moving ball hits another ball, the first ball slows down. What might that tell you about its energy?
It has less energy of motion after slowing down.
A ball rolls down a ramp and travels farther when released from a higher starting point. What might explain this?
The ball may have more energy at the bottom of the ramp, so it can travel farther.
Two identical balls are moving. Ball A is slow and Ball B is fast. Which can usually transfer more energy in a collision?
Ball B, the faster ball, can usually transfer more energy.
A metal spoon gets warm when it sits in hot soup. What kind of energy moved to the spoon?
Heat (thermal) energy.
A racer travels farther after the rubber band is wound more times. What does this observation suggest?
The extra winding transferred more energy to the racer, changing its motion.
Why might a ball move in a different direction after a collision?
The collision changes its motion; the direction depends on where and how it is hit.
When planning an investigation, why should you change one variable at a time?
So you can tell which change caused the difference in the result.
What happens to an object's energy when it moves faster?
A faster-moving object has more energy than the same object moving slower.
A battery connected by wires powers a small motor. How is energy transferred to the motor?
Energy is transferred through an electric current in the wires.
True or False: An unbalanced force transfers energy to objects.
True
Compare a fast ball and a slow ball hitting the same still ball. Predict the outcome and explain.
The fast ball will usually transfer more energy, so the still ball may move faster.
A student says, 'Energy was transferred because I saw the object move.' Is that a useful observation? Explain.
Yes. Movement is observable evidence that energy was transferred to the object.