Question

example: what is the gravitational potential energy of a 150kg object suspended 5m above the earths surface?
list knowns below
which equation do i use?
show your equation and work below
m
g
h
gpe =

Explanation:

Step1: Identify knowns

We know the mass \( m = 150\,\text{kg} \), the acceleration due to gravity \( g = 9.8\,\text{m/s}^2 \) (standard value on Earth's surface), and the height \( h = 5\,\text{m} \).

Step2: Recall GPE formula

The formula for gravitational potential energy (GPE) is \( \text{GPE} = mgh \).

Step3: Substitute values

Substitute \( m = 150\,\text{kg} \), \( g = 9.8\,\text{m/s}^2 \), and \( h = 5\,\text{m} \) into the formula:
\[
\text{GPE} = 150\,\text{kg} \times 9.8\,\text{m/s}^2 \times 5\,\text{m}
\]

Step4: Calculate the result

First, multiply \( 150 \times 9.8 = 1470 \), then multiply by \( 5 \): \( 1470 \times 5 = 7350 \). So, \( \text{GPE} = 7350\,\text{J} \) (joules, since the unit of energy here is joules, and \( 1\,\text{J} = 1\,\text{kg}\cdot\text{m}^2/\text{s}^2 \)).

Answer:

The gravitational potential energy is \( 7350\,\text{J} \), so \( \text{GPE} = \boxed{7350\,\text{J}} \) (or if we use \( g = 10\,\text{m/s}^2 \) for approximation, \( \text{GPE} = 150 \times 10 \times 5 = 7500\,\text{J} \), but the standard \( g = 9.8\,\text{m/s}^2 \) gives \( 7350\,\text{J} \)).