NEET 2020 Model Question Paper 1

Let v be velocity ecquired by the charged particle when accelerated through the potential difference V.
∴

1

2

mv2=qV
or v=√

2qV

m

As the charged particle describes a circular path of radius R in the uniform magnetic field.
∴

mv2

R

=qvB
or R=

mv

qB

=

m

qB

√

2qV

m

=

√m

B

.√

2V

q

As q, B and V remain the same.
∴R∝√m
∴

RA

RB

=√

mA

mB

⇒

mA

mB

=(

RA

RB

)2
=(

2

3

)2=

4

9