Questions from Modern Physics

Q: A marble moves along the x-axis. The potential-

A marble moves along the x-axis. The potential-energy function is shown in Fig. E7.36. (a) At which of the labeled x-coordinates is the force on the marble zero? (b) Which of the labeled x-coordinates...

Q: Figure 7.22b shows the potential ­ energy function associated with

Figure 7.22b shows the potential ­ energy function associated with the gravitational force between an object and the earth. Use this graph to explain why objects always fall toward the eart...

Q: For a system of two particles we often let the potential energy

For a system of two particles we often let the potential energy for the force between the particles approach zero as the separation of the particles approaches infinity. If this choice is made, explai...

Q: A woman stands in the middle of a perfectly smooth, frictionless

A woman stands in the middle of a perfectly smooth, frictionless, frozen lake. She can set herself in motion by throwing things, but suppose she has nothing to throw. Can she propel herself to shore w...

Q: In Example 8.4 (Section 8.2), consider

In Example 8.4 (Section 8.2), consider the system consisting of the rifle plus the bullet. What is the speed of the system’s center of mass after the rifle is fired? Explain. Example 8.4: A marksman...

Q: A cylindrical body has mass M and radius R. Can the

A cylindrical body has mass M and radius R. Can the mass be distributed within the body in such a way that its moment of inertia about its axis of symmetry is greater than MR2? Explain.

Q: The potential ­ energy function for a force

The potential ­ energy function for a force

Q: A hollow spherical shell of radius R that is rotating about an

A hollow spherical shell of radius R that is rotating about an axis through its center has rotational kinetic energy K. If you want to modify this sphere so that it has three times as much kinetic ene...

Q: In part (d) of Table 9.2, the

In part (d) of Table 9.2, the thickness of the plate must be much less than a for the expression given for I to apply. But in part (c), the expression given for I applies no matter how thick the plate...

Q: When calculating the moment of inertia of an object, can we

When calculating the moment of inertia of an object, can we treat all its mass as if it were concentrated at the center of mass of the object? Justify your answer.