
Assertion: When a bicycle is in motion, the force of friction exerted by the ground on the two wheels is always in forward direction.
Reason: The frictional force acts only when the bodies are in contact.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
C. Assertion is correct but Reason is incorrect.
D. Assertion is incorrect but Reason is correct.
Answer
161.4k+ views
Hint:Here in the Assertion it is said that force of friction exerted by the ground on the two wheels is always in forward direction that means there must not be any condition in which force of friction applied in backward direction for the Assertion to be true. Try to find that condition.
Complete answer:
There can be two cases when a bicycle is in motion:
Case1: While riding the bicycle when we applied an external force that is paddling.
Then the external force applied by us will be in backward direction and the force of friction will act in forward direction to the motion of the bicycle.
Case2: While riding the bicycle when we do not paddle or do not apply by external force.
Then there will be motion in the bicycle due to inertia and in this case the force of friction will act in backward direction to the motion of the bicycle.
Therefore, Assertion is False.
Now, we know that frictional force acts only when the two bodies are in contact.
Thus, Reason is true.
Hence, the correct answer is Option D.
Note: Be careful of the extreme words such as always, never, forever etc. while dealing with this type of questions where assertions are given. Because there will always be a possibility that it is a false statement. Whenever such words are used most of the time it is a false statement.
Complete answer:
There can be two cases when a bicycle is in motion:
Case1: While riding the bicycle when we applied an external force that is paddling.
Then the external force applied by us will be in backward direction and the force of friction will act in forward direction to the motion of the bicycle.
Case2: While riding the bicycle when we do not paddle or do not apply by external force.
Then there will be motion in the bicycle due to inertia and in this case the force of friction will act in backward direction to the motion of the bicycle.
Therefore, Assertion is False.
Now, we know that frictional force acts only when the two bodies are in contact.
Thus, Reason is true.
Hence, the correct answer is Option D.
Note: Be careful of the extreme words such as always, never, forever etc. while dealing with this type of questions where assertions are given. Because there will always be a possibility that it is a false statement. Whenever such words are used most of the time it is a false statement.
Recently Updated Pages
A steel rail of length 5m and area of cross section class 11 physics JEE_Main

At which height is gravity zero class 11 physics JEE_Main

A nucleus of mass m + Delta m is at rest and decays class 11 physics JEE_MAIN

A wave is travelling along a string At an instant the class 11 physics JEE_Main

The length of a conductor is halved its conductivity class 11 physics JEE_Main

Two billiard balls of the same size and mass are in class 11 physics JEE_Main

Trending doubts
JEE Main 2025 Session 2: Application Form (Out), Exam Dates (Released), Eligibility, & More

JEE Main 2025: Derivation of Equation of Trajectory in Physics

Electric Field Due to Uniformly Charged Ring for JEE Main 2025 - Formula and Derivation

Displacement-Time Graph and Velocity-Time Graph for JEE

Class 11 JEE Main Physics Mock Test 2025

Differentiate between audible and inaudible sounds class 11 physics JEE_Main

Other Pages
JEE Advanced Marks vs Ranks 2025: Understanding Category-wise Qualifying Marks and Previous Year Cut-offs

JEE Advanced 2025: Dates, Registration, Syllabus, Eligibility Criteria and More

Units and Measurements Class 11 Notes: CBSE Physics Chapter 1

Motion in a Straight Line Class 11 Notes: CBSE Physics Chapter 2

NCERT Solutions for Class 11 Physics Chapter 1 Units and Measurements

NCERT Solutions for Class 11 Physics Chapter 2 Motion In A Straight Line
