Unit: Magnetism and Electricity
Year: 1993 Question#: 33
Question: In the diagram below, a steel paper clip is attatched to a string, which is attached to a table. The clip remains suspended below the magnet.
As the magnet is lifted, the paper clip begins to fall as a result of
(1 ) an increase in the potential energy of the clip
(2 ) an increase in the gravitational field strength near the magnet
(3 ) a decrease in the magnetic properties of the clip
(4 ) a decrease in the magnetic field strength near the clip
What is this question really asking?
Explanation by: Nicole J
[ Return to question menu ]
Answer 1
an increase in the potential energy of the clip
INCORRECT
Potential energy is the energy that is stored and held in readiness, because it is in the stored state, it has the potential for doing work. It is like compressing a spring, when you do that it increases the potential energy of the spring and when released it does work, but not when you simply take the magnet away from the clip. return to top
Answer 2
an increase in the gravitational field strength near the clip
INCORRECT
The closer the clip and the magnet are to each other, the stronger the gravitational field, but the farther away they are, the weaker the strength ( field ). return to top
Answer 3
a decrease in the magnetic properties of the clip
INCORRECT
The magnetic properties of the paper clip never decrease or increase. They never change. By taking the magnet away from the clip, it doesn't do anything to it's magnetic properties. return to top
Answer 4
a decrease in the magnetic field strength near the clip
CORRECT
As the magnet is moved away from the clip, the magnetic field between the clip and the magnet decreases and the clip falls. return to top
What's this question really asking?
What was it that made the clip fall when the magnet was moved away from it? return to top
