Download 5. Magnets and Electromagnetism

5. Magnets and Electromagnetism
1.
If electrical charge flows in a wire, what will be present around this wire ?
2.
Object B is passed through a coil of wire from P to Q as shown below:
B
X
P
Q
Y
(a)
If a voltage is detected between X and Y, what is object B ?
(b)
What could be done with object B to make the detected voltage
bigger?
3.
Draw a diagram to show the magnetic field round a bar magnet.
4.
You will need graph paper for this question
A pupil has made an electromagnet by winding a coil of wire. The data in the
table shows the number of paperclips lifted by the electromagnet.
Current
0.5
(A)
Number
12
of
paperclips
1.0
1.5
2.0
19
29
32
2.5
3.0
3.5
4.0
60
70
80
a.
Plot the data as a line graph.
b.
Use the data to find out the number of paperclips that can be lifted
when the current is 2.5 A. You must show, on the graph, how you
obtained your answer.
c.
Other than increasing the current through the wire even more, how
could the pupil make the electromagnet stronger still?