Question

a. Find the sum of the horizontal forces on this system of wrenches. b. Find the sum of the vertical forces on this system of wrenches.c. If each of the forces is 4.0 cm from the center, find the sum of the torques about the center.

Answer 1

ANSWERS

a. 0

b. 0

c. 400Nm

EXPLANATION

a. Two horizontal forces are acting on the system of wrenches: one is acting on the top wrench to the left and the other is acting on the bottom wrench to the right and both have the same magnitude. The sum is,

$25N-25N=0N$

b. Also, there are two vertical forces in opposite directions acting on the system of wrenches, on the left and right wrenches. Hence, the sum of the vertical forces is also 0

c. All the forces are acting on the wrenches in the counterclockwise direction so, by the right-hand rule, the torque made by each of these forces is in the same direction, from the center of the system of wrenches towards the outside of the screen. And, since all the forces are the same magnitude and are at the same distance from the center, they all produce the same torque,

$\tau=25N\times0.04m=100Nm$

The sum is four times one of the torques,

$\tau_{total}=4\cdot100Nm=400Nm$