Questions from College Physics

Q: How much energy due to Earth’s magnetic field is present in 1

How much energy due to Earth’s magnetic field is present in 1.0 m3 of space near Earth’s surface at a place where the field has magnitude 0.045 mT?

Q: A biologist observes a Paramecium with a microscope whose eyepiece and objective

A biologist observes a Paramecium with a microscope whose eyepiece and objective have focal lengths 2.25 cm and 1.10 cm, respectively. The specimen is 1.18 cm from the objective lens, and the final im...

Q: The largest constant magnetic field achieved in the laboratory is about 40

The largest constant magnetic field achieved in the laboratory is about 40 T. (a) What is the magnetic energy density due to this field? (b) What magnitude electric field would have an equal energy...

Q: Five telescopes all have the same magnifying power. Given the focal

Five telescopes all have the same magnifying power. Given the focal length of the objective, rank them in order of the focal length of the eyepiece, greatest to smallest. (a) fo = 80 cm; (b) fo = 60...

Q: The outside of an ideal solenoid (N1 turns, length ℓ

The outside of an ideal solenoid (N1 turns, length ℓ, radius r) is wound with a coil of wire with N2 turns. If the current in the solenoid is changing at a rate ΔI1/Δt, what is the magnitude of the in...

Q: What is the distance between the objective and eyepiece in the Yerkes

What is the distance between the objective and eyepiece in the Yerkes telescope? (See Example 24.8.)

Q: A CRT requires a 20.0 kV amplitude power supply.

A CRT requires a 20.0 kV amplitude power supply. (a) What is the turns ratio of the transformer that raises the 170 V amplitude household voltage to 20.0 kV? (b) If the tube draws 82 W of power, fin...

Q: You have a set of converging lenses with focal lengths 1.

You have a set of converging lenses with focal lengths 1.00 cm, 10.0 cm, 50.0 cm, and 80.0 cm. (a) Which two lenses would you select to make a telescope with the largest magnifying power? What is the...

Q: A flip coil is a device used to measure a magnetic field

A flip coil is a device used to measure a magnetic field. A coil of radius r, N turns, and electrical resistance R is initially perpendicular to a magnetic field of magnitude B. The coil is connected...

Q: An electron is confined in a one-dimensional box of length

An electron is confined in a one-dimensional box of length L. Another electron is confined in a box of length 2L. Both are in the ground state. What is the ratio of their energies E2L/EL?