Questions from College Physics

Q: A coil with an internal resistance of 120 Ω and inductance of

A coil with an internal resistance of 120 Ω and inductance of 12.0 H is connected to a 60.0 Hz, 110 V rms line. (a) What is the impedance of the coil? (b) Calculate the current in the coil.

Q: The radio telescope at Arecibo, Puerto Rico, has a reflecting

The radio telescope at Arecibo, Puerto Rico, has a reflecting spherical bowl of 305 m (1000 ft) diameter. Radio signals can be received and emitted at various frequencies with appropriate antennae at...

Q: The field coils used in an ac motor are designed to have

The field coils used in an ac motor are designed to have a resistance of 0.45 Ω and an impedance of 35.0 Ω. What inductance is required if the frequency of the ac source is (a) 60.0 Hz? (b) 0.20 kHz...

Q: A projectile is launched at t = 0 with initial speed vi

A projectile is launched at t = 0 with initial speed vi at an angle θ above the horizontal. (a) What are vx and vy at the projectile's highest point? (b) Find the time t at which the pr...

Q: An eagle can determine that two light brown shrews sitting 1.

An eagle can determine that two light brown shrews sitting 1.0 cm apart on a pathway 125 m below her are in fact two shrews rather than a small rat. Assuming that only diffraction limits her ability t...

Q: A capacitor is rated at 0.025 µF. How much

A capacitor is rated at 0.025 µF. How much rms current flows when the capacitor is connected to a 110 V rms, 60.0 Hz line?

Q: The diffraction pattern of a small circular object has minima at the

The diffraction pattern of a small circular object has minima at the same angles as the diffraction pattern of a circular hole of the same diameter. By shining a laser on a sample of human blood, one...

Q: A capacitor to be used in a radio is to have a

A capacitor to be used in a radio is to have a reactance of 6.20 Ω at a frequency of 520 Hz. What is the capacitance?

Q: A white dwarf is a star that has exhausted its nuclear fuel

A white dwarf is a star that has exhausted its nuclear fuel and lost its outer mass so that it consists only of its dense, hot inner core. It will cool unless it gains mass from some nearby star. It m...

Q: An alternator supplies a peak current of 4.68 A to

An alternator supplies a peak current of 4.68 A to a coil. The voltage of the alternator is 420 V peak at 60.0 Hz. When a capacitor of 38.0 µF is placed in series with the coil, the power factor is fo...