Questions from Modern Physics

Q: In each of Examples 8.10, 8.11,

In each of Examples 8.10, 8.11, and 8.12 (Section 8.4), verify that the relative velocity vector of the two bodies has the same magnitude before and after the collision. In each case, what happens to...

Q: A spring of negligible mass has force constant k = 800 N

A spring of negligible mass has force constant k = 800 N/m. (a) How far must the spring be compressed for 1.20 J of potential energy to be stored in it? (b) You place the spring vertically with one en...

Q: Since only changes in potential energy are important in any problem,

Since only changes in potential energy are important in any problem, a student decides to let the elastic potential energy of a spring be zero when the spring is stretched a distance x1. The student d...

Q: Figure 7.22a shows the potential ­ energy function for the

Figure 7.22a shows the potential ­ energy function for the force Fx = -kx. Sketch the potential ­ energy function for the force Fx = +kx. For this force, is x = 0 a point of equi...

Q: A tennis player hits a tennis ball with a racket. Consider

A tennis player hits a tennis ball with a racket. Consider the system made up of the ball and the racket. Is the total momentum of the system the same just before and just after the hit? Is the total...

Q: An egg is released from rest from the roof of a building

An egg is released from rest from the roof of a building and falls to the ground. As the egg falls, what happens to the momentum of the system of the egg plus the earth?

Q: Explain why the points x = A and x = -A

Explain why the points x = A and x = -A in Fig. 7.23b are called turning points. How are the values of E and U related at a turning point? Fig. 7.23b:

Q: A particle is in neutral equilibrium if the net force on it

A particle is in neutral equilibrium if the net force on it is zero and remains zero if the particle is displaced slightly in any direction. Sketch the potential ­ energy function near a point of neut...

Q: The net force on a particle of mass m has the potential

The net force on a particle of mass m has the potential­ energy function graphed in Fig. 7.24a. If the total energy is E1, graph the speed v of the particle versus its position x. At what v...

Q: An apple falls from a tree and feels no air resistance.

An apple falls from a tree and feels no air resistance. As it is falling, which of these statements about it are true? (a) Only its momentum is conserved; (b) only its mechanical energy is conserved;...