Questions from Modern Physics

Q: Certain features of a person, such as height and mass,

Certain features of a person, such as height and mass, are fixed (at least over relatively long periods of time). Are the following features also fixed? (a) location of the center of gravity of the bo...

Q: During pregnancy, women often develop back pains from leaning backward while

During pregnancy, women often develop back pains from leaning backward while walking. Why do they have to walk this way?

Q: At a certain depth in an incompressible liquid, the absolute pressure

At a certain depth in an incompressible liquid, the absolute pressure is p. At twice this depth, will the absolute pressure be equal to 2p, greater than 2p, or less than 2p? Justify your answer.

Q: During the Great Mississippi Flood of 1993, the levees in St

During the Great Mississippi Flood of 1993, the levees in St. Louis tended to rupture first at the bottom. Why?

Q: A piece of iron is glued to the top of a block

A piece of iron is glued to the top of a block of wood. When the block is placed in a bucket of water with the iron on top, the block floats. The block is now turned over so that the iron is submerged...

Q: A point particle travels in a straight line at constant speed,

A point particle travels in a straight line at constant speed, and the closest distance it comes to the origin of coordinates is a distance l. With respect to this origin, does the particle have nonze...

Q: If a metal wire has its length doubled and its diameter tripled

If a metal wire has its length doubled and its diameter tripled, by what factor does its Young’s modulus change?

Q: In Example 10.10 (Section 10.6) the

In Example 10.10 (Section 10.6) the rotational kinetic energy of the professor and dumbbells increases. But since there are no external torques, no work is being done to change the rotational kinetic...

Q: As discussed in Section 10.6, the angular momentum of

As discussed in Section 10.6, the angular momentum of a circus acrobat is conserved as she tumbles through the air. Is her linear momentum conserved? Why or why not?

Q: Suppose the door of a room makes an airtight but frictionless fit

Suppose the door of a room makes an airtight but frictionless fit in its frame. Do you think you could open the door if the air pressure on one side were standard atmospheric pressure and the air pres...