DUBAI GEM PRIVATE SCHOOL
YEAR 11 GENERATOR WORKSHEET
1. Fig. 1.1 shows a coil of wire rotating steadily in the magnetic field between the poles of a
permanent magnet. The current generated in the coil is to pass through resistor R.
Fig.1.1
(a) The apparatus in Fig. 1.1 is part of an a.c. generator. What is connected between the ends A
and B of the coil and the connections C and D?
(b) (i) On Fig. 1.2, sketch a graph to show the variation with time of the current through R.
Fig 1.2
(ii) On Fig. 1.2, show the time T corresponding to one complete rotation of the coil.
[1]
[1]
2. In the laboratory demonstration shown in Fig. 2.1, a copper rod rolls at a steady speed down
the sloping parallel copper rails. The rails are in the region of a strong magnetic field that
acts vertically downwards.
Fig. 2.1
3. Fig 3.1 shows the construction of simple a.c generator. When the coil is rotated an e.m.f. is
induced in the coil.
4. A rotating-coil generator consists of a rectangular coil of wire that rotates at constant speed
between the poles of a permanent magnet. Figs. 4.1, 4.2 and 4.3 show views from one end
of the coil, when the coil is in different positions.
4.1
4.2
4.3
(b) On Fig. 4.4, sketch the graph of e.m.f. against time, for two complete rotations of the coil.
Fig.4.4
5. (a) Two coils are wound on an iron rod, as shown in Fig. 5.1. One coil is connected to a cell
and a switch. The other is connected to a sensitive centre-zero millivoltmeter.
6.A solenoid with many turns is connected across a sensitive centre-zero millivoltmeter, as
shown in Fig. 6.1.
7. Fig. 7.1 shows a thin, straight rod XY placed in the magnetic field between the poles of a
magnet. The wires from the ends of XY are connected to a centre-zero voltmeter.
8. In Fig. 8.1, XY is a copper rod placed between the N and S poles of a magnet.