Question

A book with a mass of 2.5 kg falls from a high shelf in a library. At a height of 2.0 meters its velocity is 2 m/s. What is the mechanical energy of the book?

Answers are:

5J
44J
49J
54J

Answer 1

 E=Ek+Ep = m*v^2/2 + m*g*h = 2.5*4/2 + 2.5*9.8*2 = 5+49=54J

Answer 2

Answer: 54 Joules

Explanation:

got it right in my exam