ch-13 of science

Question 1

state:

a.who discovered the the relationship between current and magnetism?

Question 2

what are magnetic fields

Question 3

what are magnetic field lines

Question 4

state the properties of field lines

Answer 4

5

Question 5

state how magnetic fields behaves due to straight conductor (include the factors)

Answer 5

3 factors

Question 6

state the max well right hand thumb rule

Question 7

______ discovered right hand rule.

Question 8

in ___ year discovery between magnetism and current happend

Question 9

_____ discovered the relationship between current and magnetism

Question 10

outside the magnet the lines goes from ___ to ____

Question 11

inside the magnet lines goes from ___ to ___

Question 12

discuss magnetic field due to circular loop conductor(include factors)

Answer 12

same factors as straight conductors

Question 13

why magnetic field lines in a circular loop appears to be straight at centre?

Question 14

what is solenoid(“definition”)

Question 15

discuss the magnetic field due to solenoid? (“include the factors “)

Answer 15

3 factors

Question 16

what happens when current carrying conductor is placed in a magnetic field

Question 17

when is the force experienced by a current carrying conductor is maximum?

Question 18

what do these indicates in flamings left hand rule:
direction of middle finger.
direction of fore finger.
direction of thumb.

Question 19

name one device that works on the magnetic effect of current.

Question 20

name the device that converts electrical energy into mechanical energy.

Question 21

a motor coverts ______ energy to ______ energy

Question 22

in flamings left hand rule, write down the three things that are at 90 degree.

Question 23

name the device which is use to reverse the direction of current in coil.

Question 24

what is the other name of spilts rings.

Question 25

what is the function of commutator in a motor,

Question 26

of what substances the brushes of motor are made.

Question 27

what is the principal of a electric motor

Answer 27

n

Question 28

in what ways the motor can made more strong .

Question 29

what is a electro motor. with the help of diagram state the working of the motor.

Question 30

name the device that converts mechanical energy into electrical energy

Question 31

which phenomenon is used in the working of ac generator .

Question 32

name the rule which gives direction of induced current.

Question 33

what type of generator is used at power station.

Question 34

what  should be changed in ac generator so that it changes into dc generator.

Question 35

explain the principal of generator

Question 36

state the ways in which induced current can be increased

Question 37

brief about electromagnetic induction

Question 38

explain the AC generator with diagram.

Question 39

how many circuits are there in house.

Question 40

state the fuse used in two circuits of house .

Question 41

list the colour of the three wires used in hour house

Question 42

what is the main purpose of the earthing

Question 43

what is electric short circuit.

Question 44

state the two hazards caused in domestic circuits.(long)

Question 45

explain why copper wire cannot be used as a fuse

Question 46

brief about domestic circuit

Question 47

brief about fuse