Answer:
Wtotal = 0
Step-by-step explanation:
- According Newton's 2nd law, the acceleration of the block is caused by the sum of all external forces acting upon it.
- If the block is moving at constant speed (so it has no acceleration along the incline), this means that the sum of all external forces is 0.
- Therefore, the work done on the block by all forces as the block moves a distance L, is just zero.
- This can be expressed also saying that as the total work done on an object by a external net force, is equal to the change in kinetic energy, if the object is moving at a constant speed, this means that there is no change in the kinetic energy, so Wtotal must be 0.