Question

A ring of diameter 7.70 cm is fixed in place and carries a charge of 5.00 mC uniformly spread over its circumference. (a) How much work does it take to move a tiny [email protected] charged ball of mass 2.50 g from very far away to the center of the ring

Answer 1

Answer:

U = 3.97 J

Explanation:

GIVEN DATA:

a = 3.85 cm

q = 3.40 mc

q =5 mc

Work done to move charge to centre of the ring is equal to potential energy of the system

$WORK DONE U = \frac{kqQ}{a}$

                 =$\frac{8.99*10^9*3.40*10^{-6} *5*10^{-6}}{3.85*10^{-2}}$

U = 3.97 J

Answer 2

Answer:

3.974 Joule

Explanation:

Diameter of ring = 7.7 cm

a = Distance from the center = d/2 = 3.85 cm = 0.0385 m

Q = Charge = 5 mC

q = Charge to move = 3.4 mC

k = Coulomb constant = 9×10⁹ Nm²/C²

Work done will be equal to Potential energy when mass is at center

$U=\frac{kQq}{a}\\\Rightarrow U=\frac{9\times 10^9\times 5\times 10^{-6}\times 3.4\times 10^{-6}}{0.0385}=3.974\ J$

∴ Work to move a tiny 3.4 mC charge from very far away to the center of the ring is 3.974 Joule