Question

A particle of mass 1 kg and charge 1 C moves from rest through a potential of 1 V. Its final velocity will be​

Answer 1

Explanation:

Initial separation between the charges r

1

=1 m

Initial potential energy U

1

=

r

1

kq

1

q

2

=

1

9×10

9

×10

−6

×2×10

−3

=18 J

Initial kinetic energy K

1

=0

Final separation between the charges r

2

=10 m

Final potential energy U

2

=

r

2

kq

1

q

2

=

10

9×10

9

×10

−6

×2×10

−3

=1.8 J

Final kinetic energy K

2

=0+

2

1

mv

2

=

2

1

(0.001)v

2

=0.0005v

2

Using energy conservation, K

2

+u

2

=K

1

+U

1

∴ 0.0005v

2

+1.8=0+18

⟹ v=180 m/s