Three blocks A, B and C, of masses 4 kg, 2 kg and 1 kg respectively, are in contact on a frictionless surface, as shown. If a force of 14 N is applied on the 4 kg block, then the contact force between A and B is:

  • Option 1)

    6 N

  • Option 2)

    8 N

  • Option 3)

    18 N

  • Option 4)

    2 N

 

Answers (1)

As we learnt in 

When 3 Blocks are in Contact -

 

- wherein

Use:F_{net}=ma

a=frac{F}{m_{1}+m_{2}+m_{3}}


f_{1}=frac{(m_{2}+m_{3})F}{m_{1}+m_{2}+m_{3}}

f_{2}=frac{m_{3}F}{m_{1}+m_{2}+m_{3}}

 

 F = m a

a = F/m = 14 |(4+2+1) = 2m| 1s

F = ma

F = (2+1) 2

F =3 \times 2 = 6 N

Contact force between A & B is used to move the bodies B & C only.


Option 1)

6 N

Correct

Option 2)

8 N

Incorrect

Option 3)

18 N

Incorrect

Option 4)

2 N

Incorrect

Most Viewed Questions

Preparation Products

Knockout NEET 2024

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 40000/-
Buy Now
Knockout NEET 2025

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 45000/-
Buy Now
Knockout NEET 2021 (One Month)

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Weekend Live Classes, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 14000/- ₹ 4999/-
Buy Now
Knockout NEET 2021

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Weekend Live Classes, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 22999/- ₹ 9999/-
Buy Now
Test Series NEET 2021

Chapter/Subject/Full Mock Tests for NEET, Personalized Performance Report, Weakness Sheet, Complete Answer Key,.

₹ 6999/- ₹ 2999/-
Buy Now
Boost your Preparation for NEET 2021 with Personlized Coaching
 
Exams
Articles
Questions