| ⇦ | 
| ⇨ |
An isolated sphere has a capacitance of 50pF. What would be the radius of the sphere?
Options
(a) 90cm
(b) 45cm
(c) 11.50cm
(d) 5.75cm
Correct Answer:
45cm
Explanation:
As potential of spherical charge (Q) having radius r is given by V = (1 / 4πε₀) (Q / r)
Also, capacitance, C = Q / V = Q / { (1 / 4πε₀) (Q / r)} C = 4πε₀r
If C = 50 × 10⁻¹² F, then
Radius of the sphere r = 50 × 10⁻¹² / 4πε₀
= 50 × 10⁻¹² × 9 × 10⁹
= 50 × 9 × 10⁻³
= 450 × 10⁻³ m
= 0.450 m = 45 cm
Related Questions: - The kinetic energy of α-particle emitted in the α-dacay of ₈₈Ra²²⁶ is
- The refracting angle of a prism is A and refractive index of the material of the prism
- If in a p-n junction, a square input signal of 10 V is applied as shown, then the output
- Two charges placed in air repel each other by a force of 10⁻⁴ N. When oil is
- Radii of curvature of a converging lens are in the rato 1:2. Its focal length
Topics: Electrostatics
(146)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- The kinetic energy of α-particle emitted in the α-dacay of ₈₈Ra²²⁶ is
- The refracting angle of a prism is A and refractive index of the material of the prism
- If in a p-n junction, a square input signal of 10 V is applied as shown, then the output
- Two charges placed in air repel each other by a force of 10⁻⁴ N. When oil is
- Radii of curvature of a converging lens are in the rato 1:2. Its focal length
Topics: Electrostatics (146)
Subject: Physics (2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
18000+ students are using NEETLab to improve their score. What about you?
Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.
Share this page with your friends
As Capacitance of Isolated sphere =4π€R
Given,
C=50picofarad
Then,
50×10(power -12)= 1/9×10(power9)×R
R=0.45m or 45cm….