Questions from Modern Physics

Q: How fast (as a percentage of light speed) would a

How fast (as a percentage of light speed) would a star have to be moving so that the frequency of the light we receive from it is 10.0% higher than the frequency of the light it is emitting? Would it...

Q: One end of an insulated metal rod is maintained at 100.

One end of an insulated metal rod is maintained at 100.0C, and the other end is maintained at 0.00°C by an ice–water mixture. The rod is 60.0 cm long and has a cross-sectional area of 1.25 cm2. The...

Q: What is the rate of energy radiation per unit area of a

What is the rate of energy radiation per unit area of a blackbody at (a) 273 K and (b) 2730 K?

Q: When sound travels from air into water, does the frequency of

When sound travels from air into water, does the frequency of the wave change? The speed? The wavelength? Explain your reasoning.

Q: Explain why it would not make sense to use a full-

Explain why it would not make sense to use a full-size glass thermometer to measure the temperature of a thimbleful of hot water.

Q: Many automobile engines have cast-iron cylinders and aluminum pistons.

Many automobile engines have cast-iron cylinders and aluminum pistons. What kinds of problems could occur if the engine gets too hot? (The coefficient of volume expansion of cast iron is approximately...

Q: In most modern wind instruments the pitch is changed by using keys

In most modern wind instruments the pitch is changed by using keys or valves to change the length of the vibrating air column. The bugle, however, has no valves or keys, yet it can play many notes. Ho...

Q: Why do frozen water pipes burst? Would a mercury thermometer break

Why do frozen water pipes burst? Would a mercury thermometer break if the temperature went below the freezing temperature of mercury? Why or why not?

Q: Why is it sometimes possible to loosen caps on screw-top

Why is it sometimes possible to loosen caps on screw-top bottles by dipping the capped bottle briefly into hot water?

Q: Like the Kelvin scale, the Rankine scale is an absolute temperature

Like the Kelvin scale, the Rankine scale is an absolute temperature scale: Absolute zero is zero degrees Rankine (0°R). However, the units of this scale are the same size as those of the Fahrenheit s...