Question

A person pushes a box. He applies a force of 400 newtons, and he pushes the box for a distance of 4 meters. After he stops pushing, the box slides forward another meter. How much work was done by the person? (1 point)
• 400 joules
• 1,600 joules
• 2,000 joules
• 100 joules

Answer 1

To calculate the work done by the person on the box, you can use the formula for work:

\[
\text{Work} = \text{Force} \times \text{Distance} \times \cos(\theta)
\]

where:
- Work is measured in joules (J),
- Force is measured in newtons (N),
- Distance is the distance over which the force is applied (in meters),
- \(\theta\) is the angle between the force and the direction of motion (0 degrees if the force is in the same direction as the motion).

Assuming the person pushes the box in the same direction as the force applied (\(\theta = 0\), so \(\cos(0) = 1\)), we can simplify the equation to:

\[
\text{Work} = \text{Force} \times \text{Distance}
\]

Given:
- Force = 400 N
- Distance = 4 m

Now, inputting the values:

\[
\text{Work} = 400 \, \text{N} \times 4 \, \text{m} = 1,600 \, \text{J}
\]

The work done by the person while pushing the box is 1,600 joules. The additional distance the box slides after the person stops pushing does not contribute to the work done by the person.

Thus, the correct answer is:

**1,600 joules**