Question

current attempt in progress
the same force f pushes in three different ways on a box moving with a velocity v, as the drawings show. rank the work done by the force f in ascending order (smallest first).
a
b
c
o a, b, c
o a, c, b
o c, b, a
o b, a, c
o c, a, b

Explanation:

Step1: Recall work - formula

The work - done formula is $W = Fd\cos\theta$, where $F$ is the force, $d$ is the displacement, and $\theta$ is the angle between the force and the displacement. Assume the displacement $d$ is the same in all cases.

Step2: Analyze case C

In case C, the force $F$ is perpendicular to the velocity (and thus the displacement) direction, so $\theta = 90^{\circ}$. Then $W_C=Fd\cos90^{\circ}=0$ since $\cos90^{\circ}=0$.

Step3: Analyze case A

In case A, the force $F$ has a component in the direction of the displacement. Let the angle between the force and the displacement be $\theta_A$ ($0^{\circ}<\theta_A < 90^{\circ}$), so $W_A = Fd\cos\theta_A$, and $0 < \cos\theta_A<1$.

Step4: Analyze case B

In case B, the force $F$ is parallel to the displacement, so $\theta_B = 0^{\circ}$ and $W_B=Fd\cos0^{\circ}=Fd$ since $\cos0^{\circ}=1$.

Step5: Rank the work - done values

Since $W_C = 0$, $0 < W_A

Answer:

C. C, A, B