Question

1) A 179‑turn circular coil of radius 3.55 cm and negligible resistance is immersed in a uniform magnetic field that is perpendicular to the plane of the coil. The coil is connected to a 13.7 Ω resistor to create a closed circuit. During a time interval of 0.121 s, the magnetic field strength decreases uniformly from 0.643 T to zero. Find the energy, in millijoules, that is dissipated in the resistor during this time interval.

energy: mJ

2) You decide to build a small generator by rotating a coiled wire inside a static magnetic field of 0.30 T. You construct the apparatus by coiling wire into 33 loops of radius 0.15 m. If the coils rotate at 2.2 revolutions per second and are connected to a device with 200Ω resistance, calculate the average power P average supplied to that device.

P average= W

3) The component of the external magnetic field along the central axis of a 46 turn circular coil of radius 11.0 cm decreases from 1.90 T to 0.400 T in 1.80 s. If the resistance of the coil is R=3.00 Ω, what is the magnitude of the induced current in the coil?

magnitude: AA

What is the direction of the current if the axial component of the field points away from the viewer?

counter-clockwise

clockwise

4) A 111 turn circular coil of radius 2.69 cm is immersed in a uniform magnetic field that is perpendicular to the plane of the coil. Over an interval of 0.127 s, the magnetic field strength increases from 54.7 mT to 96.5 mT. Find the magnitude of the average emf Eavg induced in the coil during this time interval, in millivolts.

Eavg= mV

Answer 1