What factors impact the kinetic energy of an object? (1 point)

Question

What factors impact the kinetic energy of an object? (1 point)
• Weight and height
• Mass and speed
• Weight and speed
• Mass and height

GPT-4o mini · Answer

The correct answer is **Mass and speed**. Kinetic energy is calculated using the formula $ KE = \frac{1}{2} mv^2 $, where $ m $ is the mass of the object and $ v $ is its speed. Thus, both mass and speed directly impact the kinetic energy of an object.

AYD3N · Answer

The student claims that a ball dropped 3.0 meters would have fewer than 96 joules kinetic energy upon hitting the ground. Is she correct? Why?
(1 point)
Sil have upon hitting the group, the more kinetic energy the ball O She is wrong. The higher the drop, the less kinetic the ball will have
upon hitting the ground.
She is right! The higher the drop, the greater kinetic the ball will have
upon hitting the ground.
She is right! The higher the drop, the less kinetic energy the ball will have upon hitting the ground.

GPT-4o mini · Answer

The correct response is: **She is right! The higher the drop, the greater kinetic the ball will have upon hitting the ground.** When an object is dropped from a height, it gains kinetic energy as it falls due to the conversion of potential energy to kinetic energy. The potential energy at the height can be calculated using the formula $ PE = mgh $, where $ m $ is the mass, $ g $ is the acceleration due to gravity (approximately 9.81 m/s²), and $ h $ is the height (3.0 meters in this case). As the ball falls, this potential energy converts into kinetic energy, and by the time it hits the ground, its kinetic energy will be equal to the potential energy it had at the drop height, assuming no energy is lost to air resistance. To find the kinetic energy when dropped from 3.0 meters, you would calculate: $$ KE = mgh $$ For a mass $ m $ and $ g = 9.81 \, \text{m/s}^2 $, the potential and thus the kinetic energy when reaching the ground will indeed likely be higher than 96 joules for reasonable values of mass. Thus, the student's claim is incorrect if they believe it will be less than that.

AYD3N · Answer

Kendra loves rolling down hills. She finds a steep hill to roll down. As she is rolling, when is her kinetic energy most likely the highest?
(1 point)
O just after the top of the hill right as she starts rolling down the hill
• at the bottom of the hill just as she has stopped rolling
O at the bottom of the hill right before she stops rolling
• at the top of the hill right before she has started rolling down the hill

GPT-4o mini · Answer

The correct answer is: **at the bottom of the hill right before she stops rolling.** Kinetic energy is highest when an object is moving at its maximum speed. As Kendra rolls down the hill, her potential energy is converted to kinetic energy. At the bottom of the hill, just before she stops rolling, she will have her highest speed, and therefore her kinetic energy will be at its maximum.

AYD3N · Answer

Two cars in motion have equal mass. Which car has more kinetic energy? (1 point)
• the car with the greatest volume
O the car with the greatest speed
O the car with the greatest acceleration
O the car with the greatest size

GPT-4o mini · Answer

The correct answer is: **the car with the greatest speed.** Kinetic energy is determined by the formula $ KE = \frac{1}{2} mv^2 $, where $ m $ is the mass of the object and $ v $ is its speed. Since the cars have equal mass, the car with the greater speed will have more kinetic energy, as kinetic energy increases with the square of the velocity.