Samacheer Kalvi 9th Science Magnetism and Electromagnetism Questions - 1

Question: 1

Magnetic field exists around

(A) Aluminium

(B) Iron

(C) Moving charges

(D) Static charges

Question: 2

The force on a current carrying conductor kept perpendicular in external magnetic field depends on

(A) Current in the conductor

(B) Length of the conductor

(C) Value of magnetic field

(D) All of these

Question: 3

_____ is used to change a low alternating voltage to a high alternating voltage.

(A) Electric generator

(B) Transformer

(C) Step up transformer

(D) Step down transformer

Question: 4

The generator rule is

(A) Faraday's law

(B) Fleming's right hand rule

(C) Fleming's left hand rule

(D) Right hand thumb rule

Question: 5

Transformer works on

(A) AC only

(B) DC only

(C) Both AC and DC

(D) None of these

Question: 6

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

(A) Brushes

(B) Slip rings

(C) Split rings

(D) Field magnet

Question: 7

The unit of magnetic flux density is

(A) Weber/meter²

(B) Weber meter²

(C) Weber

(D) Weber/meter