Chapter 13 – Magnetic Effects of Electric Current

Assertion: Steel core is used as an electromagnet.
Reason: Steel gets permanently magnetised when the current flows through the coil wound around.

Magnetic lines of force inside current carrying solenoid are

What should be the core of an electromagnet?

Who has stated the Right hand Thumb Rule?

The device used for producing electric current is called

To convert an AC generator into DC generator

The most important safety method used for protecting home appliances from short circuiting or overloading is

A positively-charged particle (alpha-particle) projected towards west is deflected towards north by a magnetic field. The direction of magnetic field is:

If the current values periodically from zero to a maximum value, back to zero and then reverses its direction, the current is

We can induce the current in a coil by

Forces acting on a stationery charge of in the magnetic field B is

A current through a horizontal power line flows from south to North direction. The direction of magnetic field line 0.5m above it is

A D.C generator works on the principle of

A soft iron bar is introduced inside the current carrying solenoid. The magnetic field inside the solenoid

In the domestic electric circuits, the red coloured insulated copper wire is called

When current is parallel to magnetic field, then force experience by the current carrying conductor placed in uniform magnetic field is

The factors on which one magnetic field strength produced by current carrying solenoids depends are

In electric motor, to make the coil rotating continuously in the same direction, current is reversed in the coil after every half rotation by a device called

A positively charged particle say an alpha particle projected towards west is deflected toward north by a magnetic field. The direction of the magnetic field is

The instrument that use to defect electric current in the circuit is known as

A positive charge is moving upwards in a magnetic field directed towards north. The particle will be deflected towards

At the time of short circuit, the current in the circuit

The magnetic field near a long straight wire is described by

By which instrument, the presence of magnetic field be determined?

Inside the magnet, the field lines moves

Assertion: It is fatal to touch a live electric wire as the person gets a severe electric shock. In some cases, electric shock can even kill a person.
Reason: The electric current passes through the body to the earth forming a circuit and bums the blood.

Assertion: Strength of an electromagnet depends on the magnitude of current flowing through them.
Reason: Electromagnets are majorly used for lifting heavy weights.

Which device produces the electric current?

The essential difference between A.C. generator and a D.C. generator is that

Commercial electric motors do not use