6.4.1 Torque

Question 1

Torquetorque:

Answer 1

• When a force is applied to a rotating system, the resulting angular acceleration depends not only on the magnitude of the force, but also on its direction and its point of application.
• Torque is twisting force. It is defined by the equation .
• The angular quantities w, a, and t are, in general, vectors. Their directions are defined using the right-hand convention.
• The vector definition of torque:

Question 2

Suppose a person wants to generate a great amount of torque from rotating a wheel attached to an axis. Which of the following would not increase the torque on a wheel?

Answer 2

Apply the force as close as possible to the center axis of the wheel.

Question 3

It is possible to have a net torque when ____________________.

Answer 3

sigma F = 0

Question 4

When describing torque, you must consider its direction. Which of the following is correct?

Answer 4

The direction of the torque is determined by the right-hand rule; the fingers of the right hand curl in the direction of rotation, then the exteneded thumb points in the direction of the torque or angular velocity.

Question 5

Which of the following best describes the physical quantity called torque?

Answer 5

Rotational analog of force

Question 6

Which of the following is not correct?

Answer 6

Rotational dynamics considers motion of rotation where the object considered may be though of as a particle located at its center of mass.

Question 7

Consider a rigid body with a fixed axis of rotation. Which of the following is not correct?

Answer 7

If there are no net forces acting on a body, then a net torque will not exist.

Question 8

Which of the following statements concerning torque is not correct?

Answer 8

The torque is the produce of a tangential component of the force F and the radius or position vector, r. We use sin theta, where theta is the angle from r (or the extension of r) to F. Its direction is in the plane of the force and position vector, perpendicular to the radius vector.