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Class 12
Physics
Electrostatic Potential and Capacitance
a charge of 8 mc is located at the origin calcula...

Question:
A charge of 8 mC is located at the origin. Calculate the work done in taking a small charge of -2 x 10^-9 C from a point P (0, 0, 3 cm) to a point Q (0, 4 cm, 0), via a point R (0, 6 cm, 9 cm).

Answer:

Charge located at the origin, q = 8 mC= 8 × 10 ^{- 3} C

Magnitude of a small charge, which is taken from a point P to point R to point Q, q₁ = - 2 × 10 ^{- 9}C

All the points are represented in the given figure.

Point P is at a distance, d₁ = 3 cm, from the origin along z-axis.

Point Q is at a distance, d₂ = 4 cm, from the origin along y-axis.

Potential at point P,

Potential at point Q,

Work done (W) by the electrostatic force is independent of the path.

Therefore, work done during the process is 1.27 J.

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Question:
A charge of 8 mC is located at the origin. Calculate the work done in taking a small charge of -2 x 10^-9 C from a point P (0, 0, 3 cm) to a point Q (0, 4 cm, 0), via a point R (0, 6 cm, 9 cm).

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Question: A charge of 8 mC is located at the origin. Calculate the work done in taking a small charge of -2 x 10-9 C from a point P (0, 0, 3 cm) to a point Q (0, 4 cm, 0), via a point R (0, 6 cm, 9 cm).

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Question:
A charge of 8 mC is located at the origin. Calculate the work done in taking a small charge of -2 x 10^-9 C from a point P (0, 0, 3 cm) to a point Q (0, 4 cm, 0), via a point R (0, 6 cm, 9 cm).