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1) How fast must the flux change (in weber/s) to 2 decimal places in a 0.25 m2 10-turn loop placed in a magnetic field whose maximum value is 1.75 T in order to induce an emf of V across the loop?

2) An electric generator was designed to produce an rms voltage of 120 V AC by rotating a turn loop at 3600 rpm in a constant magnetic field of 0.70 T. What is the area of the loop to the nearest cm2?

3) A metal welding unit is a very high current device. We have a unit that must produce A to weld an aluminum fixture, and it is operated from a 220 V AC outlet which has a circuit breaker that fires at 20 A. If we plug in a transformer to the 220 V and it has a primary with 100 windings, how many windings must the secondary have to obtain the desired current (just barely)?

4) A coil of diameter cm consists of 20 turns of circular copper wire 2.6 mm in diameter. A uniform magnetic field, perpendicular to the plane of the coil, changes at a rate of 3.56x10-3 T/s. The resistivity of copper is 1.68x10-8 ohm meter. Find the current in the coil to the nearest milliamp.

5) A transformer has 500 primary turns and 2200 secondary turns. The input voltage is 120 V and the output current is amps. What is the input current to the nearest tenth of an amp?

6) An inductance coil draws 2.50 A when connected to a 36.0 V battery. When connected to a 60.0 Hz , 36.0 V (rms) source, the current drawn is only A (rms). What is the value of the inductance to the nearest hundredth of a Henry?

7) An automobile has a velocity of m/s on a road where the vertical component of the earth's magnetic field 3x10-5 T. What is the potential difference between the ends of a 2 meter long axle to the nearest ten thousandth of a volt?

8) A transformer is designed to change 120 volts into volts, there are 500 turns on the primary coil how many turns are in the secondary. Assume 100% efficiency.

9) A rectangular coil of sides 3 cm and 5 cm is oriented so that its plane is perpendicular to an external magnetic field of 0.80 T pointing up. The magnetic field changes during the course of s to 0.20 T pointing down. What is the average induced emf in the coil to the nearest ten thousandth of a volt?

10) A transformer has 1000 turns in its primary and 25 turns in its secondary. The primary is connected to a 120 V, 60 Hz source. The secondary is connected to a 0.6 resistor. Calculate the current to the nearest thousandth of an amp that flows in the primary if this transformer is % efficient.