The correct response is:
By raising the height of the ski jump hill
Increasing the height of the jump hill raises the potential energy of the ski jumper.
What is one way to increase a ski jumper’s potential energy?(1 point)
Responses
By raising the height of the ski jump hill
By raising the height of the ski jump hill
By lowering the height of the ski jump hill
By lowering the height of the ski jump hill
By using shorter skis
By using shorter skis
By using longer skis
11 answers
As shown below, an object with a mass of 5 kg is moving at a speed of 10 m/s. Another object with a mass of 10 kg is moving at a speed of 5 m/s.
Which of the objects has higher kinetic energy?
(1 point)
Responses
The 10 kg object has higher kinetic energy.
The 10 kg object has higher kinetic energy.
Both objects have zero kinetic energy.
Both objects have zero kinetic energy.
The 5 kg object has higher kinetic energy.
The 5 kg object has higher kinetic energy.
The objects have equal kinetic energy.
Which of the objects has higher kinetic energy?
(1 point)
Responses
The 10 kg object has higher kinetic energy.
The 10 kg object has higher kinetic energy.
Both objects have zero kinetic energy.
Both objects have zero kinetic energy.
The 5 kg object has higher kinetic energy.
The 5 kg object has higher kinetic energy.
The objects have equal kinetic energy.
To determine which object has higher kinetic energy, we can use the formula for kinetic energy (KE):
\[ KE = \frac{1}{2} m v^2 \]
For the 5 kg object moving at 10 m/s: \[ KE_1 = \frac{1}{2} (5 , \text{kg}) (10 , \text{m/s})^2 = \frac{1}{2} (5) (100) = 250 , \text{J} \]
For the 10 kg object moving at 5 m/s: \[ KE_2 = \frac{1}{2} (10 , \text{kg}) (5 , \text{m/s})^2 = \frac{1}{2} (10) (25) = 125 , \text{J} \]
Now, comparing the two kinetic energies:
- The 5 kg object has a kinetic energy of 250 J.
- The 10 kg object has a kinetic energy of 125 J.
Therefore, the answer is:
The 5 kg object has higher kinetic energy.
Which statement best describes the relationship between a baseball’s potential and kinetic energy after it is thrown? (assume the ball travels in a straight line)(1 point)
Responses
Potential energy does not change, and kinetic energy decreases.
Potential energy does not change, and kinetic energy decreases.
Potential energy decreases as kinetic energy increases.
Potential energy decreases as kinetic energy increases.
Potential and kinetic energy both decrease.
Potential and kinetic energy both decrease.
Potential energy increases, and kinetic energy does not change.
Responses
Potential energy does not change, and kinetic energy decreases.
Potential energy does not change, and kinetic energy decreases.
Potential energy decreases as kinetic energy increases.
Potential energy decreases as kinetic energy increases.
Potential and kinetic energy both decrease.
Potential and kinetic energy both decrease.
Potential energy increases, and kinetic energy does not change.
The best statement that describes the relationship between a baseball's potential and kinetic energy after it is thrown (assuming it travels in a straight line) is:
Potential energy decreases as kinetic energy increases.
As the baseball is thrown, its height (potential energy) may decrease while its speed (kinetic energy) increases, depending on the trajectory of the throw.
A student bounces a tennis ball. She drops the ball, and then it bounces back up to her. When does the ball have zero kinetic energy?(1 point)
Responses
At the very top of its bounce
At the very top of its bounce
As soon as she drops it
As soon as she drops it
Just after it hits the ground
Just after it hits the ground
Exactly when it hits the ground
Responses
At the very top of its bounce
At the very top of its bounce
As soon as she drops it
As soon as she drops it
Just after it hits the ground
Just after it hits the ground
Exactly when it hits the ground
The correct response is:
At the very top of its bounce.
At the very top of its bounce, the ball comes to a momentary stop before falling back down, meaning it has zero kinetic energy at that point.
As shown below, a student places a 500-gram car at point X on a wooden racetrack in an energy transformation investigation.
What outcome is most likely if the student uses a 700-gram car instead?
(1 point)
Responses
A 700-gram car would have more potential energy at point X and more kinetic energy at the bottom of the racetrack
A 700-gram car would have more potential energy at point X and more kinetic energy at the bottom of the racetrack
A 700-gram car would have less potential energy at point X and less kinetic energy at the bottom of the racetrack
A 700-gram car would have less potential energy at point X and less kinetic energy at the bottom of the racetrack
A 700-gram car would have more kinetic energy at point X and less potential energy at the bottom of the racetrack
A 700-gram car would have more kinetic energy at point X and less potential energy at the bottom of the racetrack
A 700-gram car would have less kinetic energy at point X and less potential energy at the bottom of the racetrack
What outcome is most likely if the student uses a 700-gram car instead?
(1 point)
Responses
A 700-gram car would have more potential energy at point X and more kinetic energy at the bottom of the racetrack
A 700-gram car would have more potential energy at point X and more kinetic energy at the bottom of the racetrack
A 700-gram car would have less potential energy at point X and less kinetic energy at the bottom of the racetrack
A 700-gram car would have less potential energy at point X and less kinetic energy at the bottom of the racetrack
A 700-gram car would have more kinetic energy at point X and less potential energy at the bottom of the racetrack
A 700-gram car would have more kinetic energy at point X and less potential energy at the bottom of the racetrack
A 700-gram car would have less kinetic energy at point X and less potential energy at the bottom of the racetrack
The correct response is:
A 700-gram car would have more potential energy at point X and more kinetic energy at the bottom of the racetrack.
Potential energy depends on mass and height. Since the 700-gram car has a greater mass than the 500-gram car, it will have more potential energy at point X, and as it moves down the racetrack, it will convert that potential energy into kinetic energy, resulting in more kinetic energy at the bottom.
In an investigation of potential and kinetic energy, a student stands at the top of a hill and pushes a ball down the hill as shown.
How does the potential and kinetic energy of the ball change as the ball rolls down the hill?
(1 point)
Responses
The potential and kinetic energy of the ball both decrease.
The potential and kinetic energy of the ball both decrease.
The potential energy of the ball decreases, and the kinetic energy of the ball increases.
The potential energy of the ball decreases, and the kinetic energy of the ball increases.
The potential energy of the ball increases, and the kinetic energy of the ball decreases.
The potential energy of the ball increases, and the kinetic energy of the ball decreases.
The potential and kinetic energy of the ball both increase.
How does the potential and kinetic energy of the ball change as the ball rolls down the hill?
(1 point)
Responses
The potential and kinetic energy of the ball both decrease.
The potential and kinetic energy of the ball both decrease.
The potential energy of the ball decreases, and the kinetic energy of the ball increases.
The potential energy of the ball decreases, and the kinetic energy of the ball increases.
The potential energy of the ball increases, and the kinetic energy of the ball decreases.
The potential energy of the ball increases, and the kinetic energy of the ball decreases.
The potential and kinetic energy of the ball both increase.
The correct response is:
The potential energy of the ball decreases, and the kinetic energy of the ball increases.
As the ball rolls down the hill, it loses potential energy due to the decrease in height and gains kinetic energy as it speeds up.
1 answer