Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • Engineering
  • An automobile travelling with a speed of 60 Km/h, can brake to stop within a distance of 20 m. If the car is going twice as fast i.e. 120 Km/h the stopping distance (in meters) will be,<div cla

An automobile travelling with a speed of 60 Km/h, can brake to stop within a distance of 20 m. If the car is going twice as fast i.e. 120 Km/h the stopping distance (in meters) will be,

Option: 1

80


Option: 2

40


Option: 3

60


Option: 4

20


Answers (1)

best_answer

\\ \text{Case 1 :}\\ u=60 \ km/hr=\frac{60\times 1000}{60\times 60}=16.67 \ m/s \\v=0 \ m/s\\s=20 m \\ \text{From equation of motion,}\\ v^{2}=u^{2}+2as \\ 0=\left ( 16.67 \right )^{2}+2a\left ( 20 \right ) \\ \\ \Rightarrow a=\frac{-277.88}{40}=-6.94 \ m/s^{2}\\\left ( Here, \text{ sign of 'a' is negative because automobile is retarding and going to stop} \right )

\\ \text{Case 2 :}\\ u=120 \ km/hr=100/3 \ m/s=33.33 \ m/s\\v^{2}=u^{2}+2as\\0=\left ( 33.33 \right )^{2}+2(-6.94)s\\\Rightarrow s=\frac{1110.88}{13.88}=80 m

Posted by

Kuldeep Maurya

View full answer

JEE Main high-scoring chapters and topics

Study 40% syllabus and score up to 100% marks in JEE

Similar Questions

Trending Articles/News

anam-khan

CSAB NEUT counselling 2025 registration begins today for BTech admissions in NE states, UTs
anam-khan

BSEB Super 50 coaching application reopens tomorrow for JEE, NEET aspirants
anam-khan

Telangana to offer free JEE, NEET, CLAT coaching to government school students

Latest Question