Question

A charged particle of charge q and mass m is projected in a region that contains an electric and magnetic field as shown in the figure with velocity V at an angle of 45° with x-direction. If V = `sqrt((qE)/m)`, then net deviation in particle motion will be (neglect the effect of gravity) in a clockwise direction approx ______ °.

 

Options

• 70.00

• 75.00

• 80.00

• 77.00

Answer 1

A charged particle of charge q and mass m is projected in a region that contains an electric and magnetic field as shown in the figure with velocity V at an angle of 45° with x-direction. If V = `sqrt((qE)/m)`, then net deviation in particle motion will be (neglecting the effect of gravity) in a clockwise direction approx 75.00°.

Explanation:

`0.5 = (Vt)/sqrt2, t = (sqrt2 xx 0.5)/V`

`V_y = V/sqrt2 - (qE)/m xx t`

`V_y = V/sqrt2 - V^2/(sqrt2V), V_y = 0`

R = `(mV)/(qB) = (mV)/(sqrt2qB)`

`sintheta = R/(2R) = 1/2, theta = 30^circ`

Deviation = 45° + 30° = 75° clockwise