MEDIUM
7th CBSE
IMPORTANT
Earn 100

Briefly explain the construction and working of an electric bell with the help of a labeled diagram.

Important Questions on Electric Current and its Effects

MEDIUM
7th CBSE
IMPORTANT
List five uses of electromagnets.
HARD
7th CBSE
IMPORTANT
What is meant by magnetic effect of current? With the help of a labelled diagram, demonstrate the magnetic effect of current. Briefly explain Oersted’s experiment.
MEDIUM
7th CBSE
IMPORTANT
In which of the figures will the bulb glow and why?
MEDIUM
7th CBSE
IMPORTANT
Which one of the following is a stronger electromagnet? Why?
EASY
7th CBSE
IMPORTANT
_____ works on the heating effect of current.
MEDIUM
7th CBSE
IMPORTANT
Read the passage given below:
A long straight coil of wire can be used to generate a magnetic field similar to that of a bar magnet. Such coils are called solenoids, which have enormous practical applications. A solenoid usually contains a movable iron core called armature. When current flows through the wire, it generates a magnetic field around the wire. The magnetic field becomes stronger when the number of turns of wire are also increased. Solenoids are mainly used for on-off applications such as triggering, latching and locking.

Answer the following question by choosing the correct option.
The iron core in a solenoid is called

MEDIUM
7th CBSE
IMPORTANT
Read the passage given below:
A long straight coil of wire can be used to generate a magnetic field similar to that of a bar magnet. Such coils are called solenoids, which have enormous practical applications. A solenoid usually contains a movable iron core called an armature. When current flows through the wire, it generates a magnetic field around the wire. The magnetic field becomes stronger when the number of turns of wire is also increased. Solenoids are mainly used for on-off applications such as triggering, latching and locking.
Answer the following question by choosing the correct option.
When the number of turns of a wire is increased the
MEDIUM
7th CBSE
IMPORTANT

Read the passage given below:
A long straight coil of wire can be used to generate a magnetic field similar to that of a bar magnet. Such coils are called solenoids, which have enormous practical applications. A solenoid usually contains a movable iron core called armature. When current flows through the wire, it generates a magnetic field around the wire. The magnetic field becomes stronger when the number of turns of wire is also increased. Solenoids are mainly used for on-off applications such as triggering, latching and locking.

Answer the following question by choosing the correct option.
A solenoid can generate a