Divide (25,000) by (the number of miles you can walk in 1 hour).
The answer you get is the number of hours it would take you to walk around the Earth once, IF you were able to walk on water too.
Answer:
The power output of the first motor is, P = 2.0 x 10⁴ watts
Explanation:
Given data,
The height of the building, h = 10 m
The mass of the elevator, m = 1000 kg
The time duration of the motor to do this work, t = 5.0 s
The force acting on the elevator,
F = m x g
= 1000 x 9.8
= 9800 N
The work done by the elevator,
W = F x h
= 9800 x 10
= 98000 J
The power output of the first motor,
P = W / t
= 98000 / 5
= 19600 watts
= 1.96 x 10⁴ watts
Hence, the power output of the first motor is, P = 2.0 x 10⁴ watts
B) gravitational to kinetic
Explanation:
The skydiver, when he is located at a certain height h above the ground, possesses gravitational potential energy, equal to:
where m is the mass of the skydiver, g is the gravitational acceleration and h is the height above the ground. As he falls, its height h decreases, while his speed v increases, so part of the gravitational potential energy is converted into kinetic energy, which is given by
so, we see that as v increases, the kinetic energy increases. Therefore the correct answer is
B) gravitational to kinetic