Effect of electric current

Effect of electric current

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Multiple Choice

The device which is used to detect current is called a:

• Galvanometer

• Ammeter

• Motor

• Generator

Multiple Choice

How does a split ring commutator work?

• Swaps the contact evert full turn, so that the left-hand and right-hand arms of the coil always experience a force in the same direction.

• Swaps the contact evert half turn, so that the left-hand and right-hand arms of the coil do not experience a force in the same direction.

• Swaps the contact evert half turn, so that the left-hand and right-hand arms of the coil always experience a force in the same direction.

Multiple Choice

What direction is the force/motion in the following diagram?

• Perpendicular to the magnets

• Downwards

• Parallel and through the magnets

Multiple Choice

The relative strength of the magnetic field is shown by the degree of closeness of the field lines.

• false

• true

• can't say

Multiple Choice

Refer the diagram. The right face of the loop acts as North pole and left side of loop acts as south pole

• False

• True

Multiple Choice

Three bulbs A, B, C are connected in a circuit as shown in Figure, When the switch is ‘ON'

• bulb C will glow first.

• bulb B and C will glow simulaneously and bulb A will glow after some time.

• the bulbs will glow in the order A, B and C

• all the bulbs A,B and C will glow at the same time

Multiple Choice

When current is switched 'on' of a bulb it converts _______ energy into _______ energy.

• Electrical, heat

• Electrical, light

• Electrical, mechanical

• Electrical, sound

Multiple Choice

A fuse wire is a wire of-

• High resistivity and low melting point

• High resistivity and high melting point

• Low resistivity and low melting point

• Low resistivity and high melting point

Multiple Choice

When an electric current pass through by the conductors, the conductor ___________ ______

• to begin crash

• going to freeze

• heats up

• going to melt

Multiple Choice

Who discovered heating effect of elecric current?

• James Watt

• Joule-Lenz

• Michael Faraday

• Thomas Edison

Multiple Choice

Who discovered Magnetic Effect of Current:

• Faraday

• Fleming

• Newton

• Oersted

Multiple Choice

According to right hand thumb rule the direction of magnetic field in a current carrying straight conductor is denoted by:

• Thumb

• Curl fingers

• Middle finger

• First finger

Multiple Choice

What is the role of split rings in a electric motor?

• Convert A.C. into D.C.

• Convert D.C. INTO A.C.

• Reverse the direction of Current

• Increases the current

Multiple Choice

Magnetic field is maximum:

• At Two Poles

• At one pole

• At The center of the magnet

• Outside the magnet

Multiple Choice

The direction of magnetic field lines inside the magnet are:

• From North to south

• From south to north

• From North to North

• From South to South

Multiple Choice

Name the device which converts mechanical energy into electric energy

• Motor

• Generator

• Heater

• Transformer

Multiple Choice

Which of the following is not the source of magnetic field:

• Moving charge

• Electric current

• Magnet

• A small piece of iron

Multiple Choice

The device used for producing current is called a:

• Galvanometer

• Ammeter

• Motor

• Generator

Multiple Choice

The magnetic field lines near a long straight wire carrying current are:

• Straight lines

• Concentric rings

• Spiral lines

• Radial lines

Multiple Choice

A rectangular coil copper wires is rotated in a magnetic field. The direction of the induced current changes once in each:

• Two revolution

• One revolution

• Half revolution

• One-forth revolution

Multiple Choice

The magnetic field inside a long straight solenoid carry

ing current is

• Zero

• decreases as we move towards its end

• increases as we move towards its end

• the same at all points