Physics Answers

a) A +100-μC charge produces 1.5 T field 2 cm from the charge. Determine the magnitude of velocity of the charge. b) What magnetic field is produced by a charge twice that in part a) 4 cm away from it?

A 2.00-kg block is given an initial speed of 2.50 m/s up a plane inclined 15.0° with the horizontal.

The coefficient of kinetic friction between block and plane is 0.250. What speed does it have just as

it returns to its initial position?

What is a rainbow? How is it formed? Explain and be specific.

What is refraction? Why does it occur? Give examples of sound refraction and light refraction.

What is the Doppler effect? How does it work? If a star looks bluer to us than it should, is the start moving away from us or toward us? Explain.

What is the period of a sound wave whose wavelength is 2.0 meters?

What is a transverse wave? For a transverse wave, define wavelength, amplitude, period, frequency, and wave speed. What is the units of each? Explain how these characteristics are related.

Two loudspeakers are placed facing each other and driven by the same source at 680 Hz. A listener is positioned between the two speakers on the line separating them, thus creating a constructive interference at the listener's ear. What minimum distance would one of the speakers be moved back away from the listener to produce destructive interference at the listener's ear? (The speed of sound = 340 m/s.)

A heat engine is supplied with 278 k3/s of heat at a constant fixed temperature of 283°C and the best rejection takes place at 5°C The following results were reported (i) 208 klis are rejected, (ii) 139 klis are rejected, and (ii) 70 kJ/s are rejected Classify which of the results report a reversible cycle or irreversible cycle or impossible results

The period of oscillation of an irregularly shaped object is 1.2 s. Its mass is 1.0 kg and it is hanged from one of its ends to oscillate, which is 3.5 cm away from its center of mass. What is its moment of inertia?