Questions from College Physics

Q: Are entropy changes always caused by the flow of heat? If

Are entropy changes always caused by the flow of heat? If not, give some other examples of processes that increase entropy.

Q: A Compton scattering experiment is performed using an aluminum target. The

A Compton scattering experiment is performed using an aluminum target. The incident photons have wavelength λ. The scattered photons have wavelengths λ′ and energies E that depend on the scattering an...

Q: While an elevator of mass 832 kg moves downward, the tension

While an elevator of mass 832 kg moves downward, the tension in the supporting cable is a constant 7730 N. Between t = 0 and t = 4.00 s, the elevator's displacement is 5.00 m downward. What is the ele...

Q: An airplane is flying at constant speed 740 km/h in

An airplane is flying at constant speed 740 km/h in a horizontal circle of radius 4.1 km. The lift force on the wings due to the air is perpendicular to the wings. At what angle to the vertical must t...

Q: Due to the similarity between Newton’s law of gravity and Coulomb’s law

Due to the similarity between Newton’s law of gravity and Coulomb’s law, a friend proposes this hypothesis: perhaps there is no gravitational interaction at all. Instead, what we call gravity might be...

Q: The length of a spring increases by 7.2 cm from

The length of a spring increases by 7.2 cm from its relaxed length when a mass of 1.4 kg is hanging in equilibrium from the spring. (a) What is the spring constant? (b) How much elastic potential en...

Q: The K0 meson can decay to two pions: K0 → π

The K0 meson can decay to two pions: K0 → π+ + π−. The rest energies of the particles are: K0 = 497.7 MeV, π+ = π− = 139.6 MeV. If the K0 is at rest before it decays, what are the kinetic energies of...

Q: The instantaneous sinusoidal emf from an ac generator with an rms emf

The instantaneous sinusoidal emf from an ac generator with an rms emf of 4.0 V oscillates between what values?

Q: When the muscles of the eye remain tensed for a significant period

When the muscles of the eye remain tensed for a significant period of time, eyestrain results. How much is this a concern for a person using (a) a microscope, (b) a telescope, and (c) a simple magn...

Q: An electric device has the current-voltage (I-V

An electric device has the current-voltage (I-V) graph shown. What is its resistance at (a) point 1 and (b) point 2? [Hint: Use the definition of resistance.]