Question

If mass A and B are both 2.5 kg, the fulcrum is located 1.0 m to the right, mass B is located at 2.0 m to the right, and the bar

has a mass of 4.0 kg, where must mass A be located on the bar in order for the initial torque to be 0.0 Nm?
a. 0.6 m to the left of the fulcrum
C. 0.6 m to the right of the fulcrum
b. directly above the fulcrum
d. 0.2 m to the left of the fulcrum

Answer 1

To achieve an initial torque of 0 Nm, mass A must be located 0.6 m to the left of the fulcrum

Step-by-step explanation:

To find the location of mass A on the bar in order for the initial torque to be 0 Nm, we need to consider the torque balance. The torque is calculated by multiplying the force with the lever arm. Since the torque is zero, it implies that the clockwise torque is equal to the anticlockwise torque. We can calculate the torques on each side of the fulcrum using the formula: Torque = Force * Distance.

For the clockwise torque, the force is the product of mass B and acceleration due to gravity, which is 9.8 m/s². The distance is the difference between the position of mass B and the fulcrum. On the other hand, for the anticlockwise torque, the force is the product of mass A and acceleration due to gravity, and the distance is the difference between the position of mass A and the fulcrum.

Setting the clockwise torque equal to the anticlockwise torque, we can solve for the unknown position of mass A. By substituting the known values, we find that mass A must be located 0.6 m to the left of the fulcrum (option a).