An air capacitor has its plates separated by a 0.1 cm distance. The total area of the plates is 10 cm2. Identify the value of capacitor from the options given below.

This question was previously asked in
ALP CBT 2 Electronic Mechanic Previous Paper: Held on 21 Jan 2019 Shift 1
View all RRB ALP Papers >
  1. 8.85 pF
  2. 10 pF
  3. 88.5 pF
  4. 100 pF

Answer (Detailed Solution Below)

Option 1 : 8.85 pF
Free
General Science for All Railway Exams Mock Test
20 Qs. 20 Marks 15 Mins

Detailed Solution

Download Solution PDF

Concept:

The capacitance of a parallel plate capacitor is given by:

Where ϵ is the dielectric constant. For air, the value of ϵ is:

ϵ = 8.854 × 10-14 C2/N-cm2

A is the area of the cross-section of the plates 

d is the distance between the plates

Calculation:

With d = 0.1 cm, A = 10 cm2, and ϵ = 8.854 × 10-14 C2/N-cm2, the value of capacitance will be:

C = 8.854 × 10-12 F

C = 8.85 pF

Latest RRB ALP Updates

Last updated on Jul 15, 2025

-> The Railway Recruitment Board has scheduled the RRB ALP Computer-based exam for 15th July 2025. Candidates can check out the Exam schedule PDF in the article.

-> RRB has also postponed the examination of the RRB ALP CBAT Exam of Ranchi (Venue Code 33998 – iCube Digital Zone, Ranchi) due to some technical issues.

-> The Railway Recruitment Board (RRB) has released the official RRB ALP Notification 2025 to fill 9,970 Assistant Loco Pilot posts.

-> The official RRB ALP Recruitment 2025 provides an overview of the vacancy, exam date, selection process, eligibility criteria and many more.

->The candidates must have passed 10th with ITI or Diploma to be eligible for this post. 

->The RRB Assistant Loco Pilot selection process comprises CBT I, CBT II, Computer Based Aptitude Test (CBAT), Document Verification, and Medical Examination.

-> This year, lakhs of aspiring candidates will take part in the recruitment process for this opportunity in Indian Railways. 

-> Serious aspirants should prepare for the exam with RRB ALP Previous Year Papers.

-> Attempt RRB ALP GK & Reasoning Free Mock Tests and RRB ALP Current Affairs Free Mock Tests here

Hot Links: teen patti sweet teen patti star login teen patti fun teen patti game - 3patti poker