Question

If 5 uc and 100 uc charges are placed at a distance of 1 cm then the ratio of force?
2:1
1:2
1:1
none
If a single charge is doubled & the other is halved then force become:
increase
4F
unchanged D
none
​

Answer 1

Answer:

Answer is C.

Coulomb's law describes the magnitude of the electrostatic force between two electric charges. The Coulomb's law formula is given as follows.

The force between 2 charges q

1

and q

2

is given by the formula F=k

r

2

q

1

×q

2

.

Where, q

1

: Charge of object 1

q

2

: Charge of object 2

r: Distance between the two objects

F: Force between the two objects. A positive force implies a repulsive interaction, while a negative force implies an attractive interaction

k: Coulomb Constant.

In this case, the distance between 2 charges is halved. So the new force becomes F

new

=k

(

2

r

)

2

q

1

×q

2

=

r

2

4×k×q

1

×q

2

=4F.

Hence, the force between the charges becomes 4F.