Question

exam lesson name: energy conversions
exam number: 700697rr
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question 16 of 20 :
select the best answer for the question.

1. an object with a mass of 70 kilograms is supported at a height of 8 meters above the ground. whats the potential energy of the object with respect to the ground?

○ a. 2,058 j
○ b. 5,488 j
○ c. 560 j
○ d. 3,430 j

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Explanation:

Step1: Recall the formula for gravitational potential energy

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

Step2: Identify the given values

We are given that $m = 70\ kg$, $h = 8\ m$, and $g = 9.8\ m/s^2$.

Step3: Substitute the values into the formula

Substitute $m = 70$, $g = 9.8$, and $h = 8$ into the formula: $PE = 70\times9.8\times8$.
First, calculate $70\times9.8 = 686$. Then, calculate $686\times8 = 5488$. So, $PE = 5488\ J$.

Answer:

B. 5,488 J