Iesha drops a ball from three different heights, as shown.
For each drop, she calculates what the kinetic energy of the ball would be when it hits the ground. The table shows her data.
Height of Drop (meters) Kinetic Energy (joules)
1.0 48
1.5 72
2.0 96
Iesha says that a ball dropped from a height of 3.0 meters would have less than 96 joules of kinetic energy when it hits the ground. Is she correct and why?
A.
She is correct because the higher the ball is dropped from, the less kinetic energy it will have when it hits the ground.
B.
She is correct because the higher the ball is dropped from, the greater kinetic energy it will have when it hits the ground.
C.
She is incorrect because the higher the ball is dropped from, the greater kinetic energy it will have when it hits the ground.
D.
She is incorrect because the higher the ball is dropped from, the less kinetic energy it will have when it hits the ground.
C. She is incorrect because the higher the ball is dropped from, the greater kinetic energy it will have when it hits the ground.
Based on Iesha's data, the kinetic energy of the ball increases as the height of the drop increases. Therefore, a ball dropped from a height of 3.0 meters would likely have more than 96 joules of kinetic energy when it hits the ground.
The image below shows the basic construction of a hydroelectric dam. A student claims that the type of energy transformation that occurs in this system is mechanical to electrical.
image f5dad45c4b04427585e70a7062cdbdd7
Which of the following statements would BEST support the student's claim?
A.
Electricity must move to travel through power lines and reach people’s homes.
B.
The turbine must turn for electricity to flow from the generator to the power lines.
C.
Water must flow from a higher place to a lower one for electricity to be created.
D.
The electricity flowing through the power lines has enough energy to move objects.