Questions from College Physics

Q: The magnetic field due to a long straight wire carrying steady current

The magnetic field due to a long straight wire carrying steady current is measured at two points, P and Q. Where is the wire and in what direction does the current flow?

Q: A circular loop of current carries a steady current. (

A circular loop of current carries a steady current. (a) Sketch the magnetic field lines in a plane perpendicular to the plane of the loop. (b) Which side of the loop is the north pole of the magneti...

Q: In an experiment to measure the speed of sound in air,

In an experiment to measure the speed of sound in air, standing waves are set up in a narrow pipe open at both ends using a speaker driven at 702 Hz. The length of the pipe is 2.0 m. What is the air t...

Q: Computer speakers that are intended to be placed near a CRT computer

Computer speakers that are intended to be placed near a CRT computer monitor are magnetically shielded—either they don't use magnets or they are designed so that their magnets produce only a small mag...

Q: The potential difference across a cell membrane from outside to inside is

The potential difference across a cell membrane from outside to inside is initially at −90 mV (when in its resting phase). When a stimulus is applied, Na+ ions are allowed to move into the cell such t...

Q: Explain why there is almost no hydrogen (H2) or helium

Explain why there is almost no hydrogen (H2) or helium (He) in Earth's atmosphere, yet both are present in Jupiter's atmosphere. [Hint: Escape velocity from Earth is 11.2 km/s and escape velocity from...

Q: The nucleus of a helium atom contains two protons that are approximately

The nucleus of a helium atom contains two protons that are approximately 1 fm apart. How much work must be done by an external agent to bring the two protons from an infinite separation to a separatio...

Q: To make an order-of-magnitude estimate of the energy

To make an order-of-magnitude estimate of the energy level spacings in the nucleus, assume that a nucleon is confined to a one- dimensional box of width 10 fm (a typical nuclear diameter). Calculate t...

Q: Small animals eat much more food per kilogram of body mass than

Small animals eat much more food per kilogram of body mass than do larger animals. The basal metabolic rate (BMR) is the minimal energy intake necessary to sustain life in a state of complete inactivi...

Q: An AM radio station broadcasts at 570 kHz. (a

An AM radio station broadcasts at 570 kHz. (a) What is the wavelength of the radio wave in air? (b) If a radio is tuned to this station and the inductance in the tuning circuit is 0.20 mH, what is t...