Question

the illustration shows a crane which lifted a girder with a force of 1,200 n. how much work was done on the girder? oa 18,000 j ob 24,000 j oc 42,000 j od 48,000 j

Explanation:

Step1: Recall the formula for work

Work \(W = F\times d\), where \(F\) is the force and \(d\) is the displacement in the direction of the force.

Step2: Determine the displacement in the direction of the force

The force is applied in the vertical direction. The vertical displacement \(d=15 + 20=35\space m\). The horizontal displacement (40 m) does not contribute to the work done against gravity (since force and displacement are perpendicular for horizontal motion in this context). The force \(F = 1200\space N\).

Step3: Calculate the work done

Substitute \(F = 1200\space N\) and \(d = 35\space m\) into the work formula \(W=F\times d\). So \(W=1200\times35 = 42000\space J\)

Answer:

C. 42,000 J