Question

A. A person does 5415J of work in 4.5 minutes, how much power, expressed in watts, rounded to the tenths place, was generated?

B. Calculate the potential energy of an object whose mass is 56.90kg when dropped from a height of 2150.cm. Round your answer to the nearest tens place.
C. Calculate the kinetic energy of an object with a mass of 355g moving at a velocity of 7.73 m/s. Round your answer to the nearest tenths place.
D. What is the total energy of a system with KE = 1368 J and a PE = 5782J? Express your answer in kJ.

Answer 1

Answer: I only have the answer for A, but still, the answer is 20.07.

1. Explanation: Because the number ends in a 15, round to the nearest tenth which is 20. So now the number is 5420.
2. To get the Watts (W) you have to take 5420 and divide it by the time in seconds. 4.5 minutes in seconds is 270, so 5420 divided by 270 equals 20.07.
3. So 20.07 is the answer.