A man pushes a block with a force of 20 newtons across a surface for 5 meters. What is the total work done by the man?

To determine the total work done by the man pushing the block, we can use the formula for work, which is expressed as:

Work = Force × Distance × cos(θ)

In this scenario, the force applied is 20 newtons, and the distance the block is pushed is 5 meters. Since the force is applied in the direction of the movement, the angle (θ) between the force vector and the displacement vector is 0 degrees. The cosine of 0 degrees is 1.

Now, substituting the values into the formula:

Work = 20 N × 5 m × cos(0)

Work = 20 N × 5 m × 1

Work = 100 joules

Thus, the total work done by the man in this situation is 100 joules. This is why the answer is correct. The calculation shows that the work done is a direct product of the force applied over a certain distance in the direction of that force.