Physic Practice Exam

A wrench is used to tighten a nut. A 15N perpendicular force is applied 50cm away from the axis of rotation, and moves a distance of 10 cm as it turns. What is the torque applied to the wrench?

• 7.5 Nm
• 1.5 Nm
• 750 Nm
• 150 Nm

The property of a body to resist change in motion.

• mass
• weight
• volume
• inertia

Which best describes moment of inertia?

• Measure of an object's resistance to changes in its rotation speed
• The distance an object travels in a circular motion
• The force required to rotate an object
• A measure of an object's translational speed

Which equation defines rotational kinetic energy?

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The moment of inertia for a diver doing a flip is smallest when:

• The diver is in a pike position (legs straight out, hands touching toes)

• The diver is fully laid out (Body straight – arms at sides)

• When the diver is in a tuck position. (knees to chest, arms around knees)

• The diver performs in a wolf position (one leg extended straight out, other leg bent at the knee pointed in the opposite direction, arms at side)

In what direction should a given force be applied to an object to produce maximum

       torque?

• perpendicular to the lever arm

• parallel to the lever arm

• at some angle between 0° and 90° relative to the lever arm

• at some angle between 90° and 180° relative to the lever arm

The moment of inertia for a rotating object depends on:

• the mass of the object and its angular speed

• The mass of the object and how the mass is distributed about the axis of rotation

• the angular speed of an object

• the mass of the object

Angular Momentum is the product of...

• rotational inertia and linear velocity.

• linear inertia and angular velocity.

• linear momentum and angular velocity

• rotational inertia and angular velocity.

The "power" of a machine measures...

• The work it does

• The force it produces

• The rate of doing work

• Its strength

What are the two factors that affect the momentum of an object?

• speed and velocity

• time and mass

• distance and displacement

• mass and velocity