Question

A current of 12.5 mA is maintained in a single circular loop with a circumference of 2.55 m. A magnetic field of 0.750 T is directed parallel to the plane of the loop. What is the magnitude of the torque exerted by the magnetic field on the loop

Answer 1

Answer:

Torque $= 4.856 * 10^{-3}$ Nm

Explanation:

Torque can be calculated by using below given relation

$T= BIA$ ---------- Equation (1)

Where T is the torque in Nm

B is the magnetic field in Tesla

I is the current in Ampere

and A is the area in square meter

Since the current is flowing in circular loop, its area will be equal to $A = \pi r^2$

Circumference $= 2 \pi r$

$2.55 = 2 * 3.14 * r\\r = \frac{2.55}{2*3.14} \\r = 0.406$

Substituting the value of r in the formula of area we get -

$A = 3.14 * (0.406)^2\\A = 0.518$

Substituting all the values in equation 1

$T= 0.75 * 12.5 * 10^{-3} * 0.518 \\T = 4.856 * 10^{-3}$