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A proton (mass= 1.67×10-27 kg, charge= 1.6×10-19 C) travelling with speed 1×106 m/s enters a region of space containing a uniform magnetic field of 1.2 T. What is the time t required for the proton to re-emerge into the field-free region? t =

User Vatsal
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2 Answers

1 vote

Answer:

The time required for the proton to re-emerge into the field-free region is 5.47 x 10⁻⁸ s

Step-by-step explanation:

given;

mass of proton, m = 1.67 × 10⁻²⁷ kg

charge of proton, q = 1.6 × 10⁻¹⁹ C

speed of proton, v = 1 × 10⁶ m/s

uniform magnetic field, B = 1.2 T

Force on the proton due to uniform magnetic field = qvB

Force on the proton in the circular region = ma = mv²/r

The time required for the proton to re-emerge into the field-free region, is the same as the time required for the proton to return to its starting position. During this period, the proton has made one complete revolution.

v = 2πr/t

t = 2πr/v

where;

t is the required for the proton to re-emerge into the field-free region

r is the radius of the circular region

mv²/r = qvB

r = mv²/qvB

r = mv/qB

r = (1.67 × 10⁻²⁷ x 1 × 10⁶) / (1.6 × 10⁻¹⁹ x 1.2)

r = 8.698 x 10⁻³ m

t = 2πr/v

t = (2π x 8.698 x 10⁻³) / (1 × 10⁶)

t = 5.47 x 10⁻⁸ s

Therefore, the time required for the proton to re-emerge into the field-free region is 5.47 x 10⁻⁸ s

User Jeff Nyak
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5.8k points
3 votes

Answer:

The time taken will be 2.73*10^(-8) sec

Step-by-step explanation:

After the proton enters in to a magnetic field, it follows circular motion in a clockwise direction.

Proton will re-emerge into the field free region, when it has completed semi circle.

Let the time required be t sec

Force = qv*B

centripetal force= mv^2/r

Now taking both the equations

r = mv/ qB = 8.7*10^(-3) m

Total distance traveled will be= pi*r

And, total time taken will be t = pi*r / v = 2.73*10^(-8) sec

User Courtney Pattison
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