Answer: when an object begins to fall its potential energy decreases and it’s kinetic energy increases, potential energy is equal to kinetic energy because a decrease in potential energy is exactly equal to the increase in kinetic energy.
A hydroelectric dam or a hydro-power plant.<span />
Answer: option (D)
Explanation:
The potential energy of each of the students is given below as
P.E(student A) = mgh, where m = mass of student A, g is acceleration due to gravity and h = height of the high dive structure.
The mass of student B is twice as much as that of A, hence his mass is 2m and his potential energy is given below as
P.E ( student B) =2mgh = 2(mgh)
Recall that the relationship between potential energy and work done is that
Work done = - (change in potential)
For student A, work done = - mgh
For student B, work done = - 2mgh
From the equations above it can be seen that student B will do twice the work in getting to the high dive structure than student A hence validating option D.
