Question

1. an object of mass 5.0 kg is lifted vertically upward by 2.0 m. assuming the acceleration due to gravity is 9.8 m/s², how much work is done against gravity?

a. 10 j b. 20 j
c. 49 j d. 98 j

Explanation:

Step1: Recall the formula for work done against gravity

The work done against gravity is given by the formula \( W = mgh \), where \( m \) is the mass, \( g \) is the acceleration due to gravity, and \( h \) is the height lifted.

Step2: Substitute the given values into the formula

We have \( m = 5.0 \, \text{kg} \), \( g = 9.8 \, \text{m/s}^2 \), and \( h = 2.0 \, \text{m} \).
Substituting these values into the formula:
\( W = 5.0 \, \text{kg} \times 9.8 \, \text{m/s}^2 \times 2.0 \, \text{m} \)

Step3: Calculate the work done

First, multiply \( 5.0 \) and \( 9.8 \): \( 5.0 \times 9.8 = 49 \)
Then, multiply the result by \( 2.0 \): \( 49 \times 2.0 = 98 \)
So, the work done against gravity is \( 98 \, \text{J} \).

Answer:

D. 98 J