Questions from College Physics

Q: The Sun delivers an average power of 1370. W/m2

The Sun delivers an average power of 1370. W/m2 to the top of Earth’s atmosphere. Find the magnitudes of E(max and B(max for the electromagnetic waves at the top of the atmosphere.

Q: A laser beam is used to levitate a metal disk against the

A laser beam is used to levitate a metal disk against the force of Earth’s gravity. (a) Derive an equation giving the required intensity of light, I, in terms of the mass m of the disk, the gravitatio...

Q: A microwave oven is powered by an electron tube called a magnetron

A microwave oven is powered by an electron tube called a magnetron that generates electromagnetic waves of frequency 2.45 GHz. The microwaves enter the oven and are reflected by the walls. The standin...

Q: Consider a bright star in our night sky. Assume its distance

Consider a bright star in our night sky. Assume its distance from the Earth is 20.0 light - years (ly) and its power output is 4.00 x 1028 W, about 100 times that of the Sun. (a) Find the intensity of...

Q: What are the wavelengths of electromagnetic waves in free space that have

What are the wavelengths of electromagnetic waves in free space that have frequencies of (a) 5.00 x 1019 Hz and (b) 4.00 x 109 Hz?

Q: A type of mirage called a pingo is often observed in Alaska

A type of mirage called a pingo is often observed in Alaska. Pingos occur when the light from a small hill passes to an observer by a path that takes the light over a body of water warmer than the air...

Q: A diathermy machine, used in physiotherapy, generates electromagnetic radiation that

A diathermy machine, used in physiotherapy, generates electromagnetic radiation that gives the effect of “deep heat” when absorbed in tissue. One assigned frequency for diathermy is 27.33 MHz. What is...

Q: What are the wavelength ranges in (a) The AM

What are the wavelength ranges in (a) The AM radio band (540–1600 kHz) and (b) The FM radio band (88–108 MHz)?

Q: An important news announcement is transmitted by radio waves to people who

An important news announcement is transmitted by radio waves to people who are 100. km away, sitting next to their radios, and by sound waves to people sitting across the newsroom, 3.0 m from the news...

Q: The rainbow of visible colors in the electromagnetic spectrum varies continuously from

The rainbow of visible colors in the electromagnetic spectrum varies continuously from the longest wavelengths (the reddest colors) to the shortest wavelengths (the deepest violet colors) our eyes can...