Final answer:
The work done by the force on a 2kg block pushed up a vertical wall with constant velocity is 39.2 J, which is calculated using the work formula and gravitational force. The provided options do not include this answer, indicating a possible error in the options given.
Step-by-step explanation:
The question asks about the work done on a 2kg block that is pushed up a vertical wall with constant velocity. Since the block is moving at a constant velocity, the force applied to it is exactly balancing the gravitational force acting downwards. To calculate the work done by the applied force, we use the work formula Work (W) = Force (F) × Distance (d) × cos(θ), where θ is the angle between the force and the displacement. Here, the force is applied vertically to counteract gravity, thus the angle θ = 0 degrees, and cos(0)=1. The gravitational force on the block is equal to its weight, F = mg, where m is the mass of the block and g is the acceleration due to gravity (9.8 m/s²).
Thus, the force required to push the block at a constant velocity is F = 2kg × 9.8 m/s² = 19.6 N. The work done by this force over a distance of 2 meters is W = 19.6 N × 2m = 39.2 J. Since none of the provided options match the calculated work done, it seems there may be an error in the question or the options provided.