Question

question 1 of 26
which object has the most gravitational potential energy?
a. a 8 kg book at a height of 2 m
b. a 5 kg book at a height of 2 m
c. an 8 kg book at a height of 3 m
d. an 5 kg book at a height of 3 m

Explanation:

Step1: Recall the formula for gravitational potential energy

The formula for gravitational potential energy is \(U = mgh\), where \(m\) is the mass, \(g\) is the acceleration due to gravity (\(g = 9.8\space m/s^{2}\)), and \(h\) is the height.

Step2: Calculate the gravitational potential energy for each option

• Option A: \(m = 8\space kg\), \(h=2\space m\). Then \(U_{A}=mgh = 8\times9.8\times2=156.8\space J\)
• Option B: \(m = 5\space kg\), \(h = 2\space m\). Then \(U_{B}=mgh=5\times9.8\times2 = 98\space J\)
• Option C: \(m = 8\space kg\), \(h = 3\space m\). Then \(U_{C}=mgh=8\times9.8\times3=235.2\space J\)
• Option D: \(m = 5\space kg\), \(h = 3\space m\). Then \(U_{D}=mgh=5\times9.8\times3 = 147\space J\)

Answer:

C. An 8 kg book at a height of 3 m