chapter 8
What is meant by the "lever arm" of a torque?
It is the distance between the point at which a force is applied and the rotational axis. √It is the perpendicular distance from the rotational axis to the line along which the force acts. It is the distance between the point at which a force is applied and the center of mass of an object. It is the angle between the applied force vector and the rotational axis. SubmitMy AnswersGive Up
As distance increases between most of the mass of an object and its center of rotation, how does rotational inertia change? As distance increases between most of the mass of an object and its center of rotation, how does rotational inertia change?
It stays the same. It goes to zero. It decreases. √It increases.
When Dr. Hewitt cuts the broom right through the center of gravity, how do the weights of the two sides of the broom compare? When Dr. Hewitt cuts the broom right through the center of gravity, how do the weights of the two sides of the broom compare?
The longer side (the handle) has a greater weight than the bristle side. Both sides of the broom on either side of the center of gravity have equal weight. √ The shorter side, where the bristles of the broom are, has a greater weight than the handle.
What does a torque tend to do to an object?
Torque tends to decrease the rotational inertia of the object. √ Torque tends to twist or change the state of rotation of the object. Torque tends to increase the rotational inertia of the object. Torque tends to increase the linear speed of the object.
Consider three axes of rotation for a pencil: along the lead, at right angles to the lead at the middle, and at right angles to the lead at one end. Rate the rotational inertias about each axis from smallest to largest.
√Axis along the lead, through the center, through one end Axis along the lead, through one end, through the center Axis through the center, through one end, along the lead Axis through one end, along the lead, through the center
How does the torque due to the weight of one side of the broom exerted around the balance point compare with the torque exerted by the weight of the other side of the broom around the balance point? How does the torque due to the weight of one side of the broom exerted around the balance point compare with the torque exerted by the weight of the other side of the broom around the balance point?
The torque due to the weight of the shorter side (the bristles of the broom) is smaller in magnitude than the torque due to the weight of the longer side, and opposite in direction. √ The torque due to the weight of the shorter side (the bristles of the broom) is equal in magnitude to the torque due to the weight of the longer side, and opposite in direction. The torque due to the weight of the shorter side (the bristles of the broom) is larger in magnitude than the torque due to the weight of the longer side (the handle), and opposite in direction. SubmitHintsMy AnswersGive UpReview Part
