The answer is E but I don’t get why diagram 1 is included in work done by F when it does not show possibility for displacement.
Hi, I think the answer should be D.
Work is only done when a force is applied and a body moves for a distance in the direction of the force.
Diagram 1
The person is siting on a chair. There is a force (weight) but there is NO movement in any body (person nor chair). So the force is not doing any work. Therefore, diagram 1 would not be in any column.
Diagram 2
The wheelbarrow is being lifted upwards in the direction of the force. So work is being done by the force ‘F’. However, the distance (d) labelled on the diagram is not the distance moved by the force. The distance labelled is perpendicular to the direction of the force. Hence, work done = F x d, does not apply to this diagram.
Diagram 2 will be in the first column but not in the second column.
Diagram 3
The pulley is pulling the weight upwards by applying force’F. The weight moves by the distance ‘d’ as the distance labelled is in the direction of the force. Hence, the formula work done = F x d, is applicable in this case.
Diagram 3 would be in the first and second column.
Hey you right. I had to look it up again and the answer is indeed D. (From bmat 2012)
