Question
There is a current in a wire. The direction of the current is out of the page.
Which diagram shows the magnetic field pattern produced?
Answer/Explanation
Ans:B
Question
Two magnets are placed near a current-carrying coil.
The diagram shows this experimental arrangement and the current direction in the coil.
Which statement is correct?
- Both X and Y are attracted to the coil.
- Both X and Y are repelled by the coil.
- X is attracted to the coil and Y is repelled.
- X is repelled by the coil and Y is attracted.
Answer/Explanation
Ans:
B
Question
When a current-carrying conductor is placed in a magnetic field, it experiences a force.
Which statement about this force is correct?
- It is parallel to both the magnetic field and the direction of the current.
- It is parallel to the magnetic field and perpendicular to the direction of the current.
- It is perpendicular to the magnetic field and parallel to the direction of the current.
- It is perpendicular to both the magnetic field and the direction of the current.
Answer/Explanation
Ans:
D
Question
Three cores of different metals P, Q and R are placed inside identical coils of wire.
At least one of the metals is non-magnetic.
The cores are held above some iron nails.
The three diagrams show what happens when there is a current in the coils.
The three diagrams below show what happens when the current is then switched off.
Which core metals are magnetic?
A P only
B R only
C P and Q
D Q and R
Answer/Explanation
Ans: D
Question
A solenoid is connected to a very sensitive ammeter. A rod is inserted into one end of the solenoid. The ammeter shows that there is a small electric current in the solenoid while the rod is moving.
Which rod is being inserted?
a heated copper rod
a magnetised steel rod
an uncharged nylon rod
a radioactive uranium rod
Answer/Explanation
Ans: B