A motor is designed to operate on 117 V and draws a current of 12.2 A when it first starts up. At its normal operating speed, the motor draws a current of 2.30 A. Obtain (a) the resistance of the armature coil,(b) the back emf developed at normal speed, and (c) the current drawn by the motor at one-third of the normal speed.

In a 240-turn automobile alternator, the magnetic flux in each turn is = 2.50 x 104 cos wt, where is in webers, w is the angular speed of the alternator, and this in seconds. The alternator is geared to rotate five times for each engine revolution. The engine is running at an angular speed of 1.00 x 10³ rev/min. (a) Determine the induced emf in the alternator as a function of time. (Assume & is in V.) & 30.1593 sin (523.5988) X (b) Determine the maximum emf in the alternator. 30.1593 X What are the maximum values of the sine and cosine functions? V

A 1.80-H inductance coil and a 11.2 2 resistor are connected in series with a battery whose emf is 115 V and a switch. Initially, the switch is open. At t = 0, the switch is closed. (a) Determine the rate at which energy is stored in the magnetic field at t = 0.170 s. 94.93 x At what rate is energy stored in the magnetic field at the given time? W (b) Determine the rate at which thermal energy is dissipated through the resistance at t = 0.170 s. W (c) Determine the rate at which the battery delivers energy at t = 0.170 s. W

A conducting rod of length 1.58m moves with a velocity 34.7m/s parallel to a long wire carrying a steady current of 21.9 mA. The axis of the rod is maintained perpendicular to the wire with the near end a distance 8.03cm away. Calculate the magnitude of the emf induced in the rod. Submit Answer Tries 0/10