San Francisco a very simple technique is used to turn around a cable car when it reaches the end of its route. The car rolls onto a turntable, which can rotate about a vertical axis through its center. Then, two people push perpendicularly on the car, one at each end. The turntable is rotated one-half of a revolution to turn the car around. If the length of the car is 7.00 m and each person pushes with a 175 N force, what is the magnitude of the net torque applied to the car?
2 x (7.00/2)x 175 N-m
To find the magnitude of the net torque applied to the car, we need to use the formula for torque:
Torque = Force x Lever Arm
The lever arm is the distance from the axis of rotation (the center of the turntable) to the point where the force is applied. Since the forces are applied perpendicularly at each end of the car, the lever arm would be half of the length of the car (7.00 m / 2 = 3.50 m).
Now, we can calculate the torque for each person pushing on the car:
Torque per person = Force x Lever Arm = 175 N x 3.50 m = 612.5 N-m
Since there are two people pushing on the car, we need to double the torque calculated above:
Total torque = 2 x Torque per person = 2 x 612.5 N-m = 1225 N-m
Therefore, the magnitude of the net torque applied to the car is 1225 N-m.