Torque

As shown above, a rod with a length L is free to rotate about point A. An external force F is applied perpendicular to the rod. In which of the following cases is the torque on the rod the same as the above?

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Two masses of mass 10.0 and 6.0 kg are hung from massless strings at the end of a light rod. The rod is virtually weightless. A pivot (fulcrum) is placed off center and the system is free to rotate. If the 6.0 kg mass is 4.0 m away from the pivot, how far away is the 10.0 kg mass if the system is not rotating?

• 0.42 m

• 2.4 m

• 4.8 m

• 4.2 m

Two masses of mass 10.0 and 6.0 kg are hung from massless strings at the end of a light rod. The rod is virtually weightless. A pivot (fulcrum) is placed off center and the system is free to rotate. If the string supporting the 10 kg mass is cut, find the net torque of the system.

• 24 Nm

• 60 Nm

• 240 Nm

• 480 Nm

1. Which of the following must be true for the system of two concentric massless pulleys and two masses shown in the picture for the system to be at equilibrium?

• m₁ = m₂

• m₁R₁ = m₂R₂

• m₁R₂ = m₂R₁

• m₁R₁² = m₂R₂²

Two wheels are fixed to each other and are free to rotate about a frictionless axis through their concentric centers. Four forces are exerted tangentially to the wheels. The magnitude of the net torque is:

• zero

• FR

• 2FR

• 4FR

Two wheels are fixed to each other and are free to rotate about a frictionless axis through their concentric centers. Four forces are exerted tangentially to the wheels. As a result of the net torque on the wheels, the wheels will rotate-

• clockwise

• counterclockwise

Where should another 4 N force be applied to maximize the net torque on the object?

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Where should another 4 N force be applied to place the block in an equilibrium state?

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Tags

NGSS.HS-PS2-1