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A charged particle with a charge-to-mass ratio of |q|/m = 5.7 × 108 C/kg travels on a circular path that is perpendicular to a magnetic field whose magnitude is 0.84 T. How much time does it take for the particle to complete one revolution?

Respuesta :

Answer:

1.312 x [tex]10^{-8}[/tex] s.

Explanation:

Given:

charge-to-mass ratio of "|q|/m" = 5.7 × 108 C/kg

magnetic field 'B'= 0.84T

We know that radius 'r' of the circular path of a charged particle 'q' of mass 'm', moving at constant speed 'v', in a uniform magnetic field 'B' can be defines as

r= mv / |q|B

so, v = (|q| B r)/m -->eq1

Now, also  the linear velocity of a particle undergoing circular motion can be defined as

v= 2πr / t

so, t =  2πr / v

where,

2πr = total distance covered in one full revolution

t = time taken for one full revolution

Putting the value of v from eq 1 in above equation

therefore,

t= 2πr / ([tex]\frac{|q|}{m}[/tex] B r)

t=  2π / ( [tex]\frac{|q|}{m}[/tex]B )

t= 2π / (5.7 x [tex]10^{8}[/tex] x 0.84)

t= 1.312 x [tex]10^{-8}[/tex] s.

Therefore, it took  1.312 x [tex]10^{-8}[/tex] s  for the particle to complete one revolution.

Answer:

Time to complete one revolution = 1.31 x 10^(-8) s

Explanation:

In motion of charges in electromagnetic fields, we know that ;

R = mv/qB

Where,

R is radius of the circular path

q is the charge on the particle

m is the mass of the particle moving v is constant speed

B is magnetic field

Now in the question, we are given value of q/m. Let's rearrange the equation to show that;

r = mv/qB

(q/m)•(rB) = v - - - - (1)

Now, in circular motion, we know that; Period; T = 2πr/v

Thus, let's make v the subject.

v = 2πr/T - - - - - (2)

Now equating eq 1 to eq 2,we obtain;

(q/m)•(rB) = 2πr/T

r will cancel out to give ;

(q/m)B = 2π/T

Making T the subject, we get;

T = 2π/[(q/m)B]

From the question,

B = 0.84 T

q/m = 5.7 × 10^(8) C/kg

Thus,

T = 2π/[5.7 × 10^(8) x 0.84] = 1.31 x 10^(-8) s

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