#### Magnetism and Electromagnetism English Medium Free Online Test 1 Mark Questions with Answer Key 2020 - 2021

9th Standard

Reg.No. :
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Science

Time : 00:10:00 Hrs
Total Marks : 10

Part A

10 x 1 = 10
1. Which of the following converts electrical energy into mechanical energy?

(a)

motor

(b)

battery

(c)

generator

(d)

switch

2. An electric generator converts

(a)

electrical energy into mechanical energy

(b)

mechanical energy into heat energy

(c)

electrical energy into electrical energy

(d)

mechanical energy into electrical energy

3. The part of the AC generator that passes the current from the armature coil to the external circuit is

(a)

field magnet

(b)

split rings

(c)

slip rings

(d)

brushes

4. Transformer works on.

(a)

AC only

(b)

DC only

(c)

bothAC and DC

(d)

AC nor effectively than DC

5. The unit of magnetic flux density is

(a)

weber

(b)

weber/metre

(c)

weber/metre2

(d)

weber. metre2

6. The direction of magnetic field around a straight conductor carrying current can be determined by____________

(a)

Fleming's left hand rule

(b)

Lenz's law

(c)

Right hand thumb rule

(d)

Fleming's right hand rule

7. The magnetic field produced due to a circular wire at its centre is_________

(a)

at 45° to the plane of the wir

(b)

at 60° to the plane of the wire

(c)

in the plane of the wire

(d)

perpendicular to the plane of the wire

8. A magnetic field exerts no force on________

(a)

stationary electric charge

(b)

a magnet

(c)

an electric charge moving perpendicular to its direction

(d)

an unmagnetised iron bar

9. At the  centre of a magnet, the magnetism is____________

(a)

zero

(b)

same as the poles

(c)

maximum

(d)

minimum

10. Induced current flows through a coil__________

(a)

more that the period during which flux changes through it.

(b)

less than the period during which flux changes through it

(c)

only for the period during which flux changes through it

(d)

None of the above