Given below are two statements:
Assertion (A): A standing bus suddenly accelerates. If there was no friction b

Question

Given below are two statements:
Assertion (A): A standing bus suddenly accelerates. If there was no friction between the feet of a passenger and the floor of the bus, the passenger would move back.
Reason (R): In the absence of friction, the floor of the bus would slip forward under the feet of the passenger.

Accepted Answer

1. **Analyze the Physics (Inertia):** According to Newton's First Law of Motion (Law of Inertia), a body at rest tends to remain at rest unless acted upon by an external force. 
2. **Analyze the Forces:** When the bus accelerates suddenly, the floor of the bus moves forward. If there is **no friction** between the feet and the floor, there is no horizontal external force to accelerate the passenger's body forward along with the bus. 
3. **Evaluate Reason (R):** Consequently, the floor of the bus slips forward under the feet of the passenger. This statement is **True** [1].
4. **Evaluate Assertion (A):** Since the passenger remains at rest relative to the ground (due to inertia) while the bus moves forward, the passenger moves backward **relative to the bus**. This statement is **True**.
5. **Establish the Link:** The backward motion relative to the bus occurs *because* the floor slips forward while the passenger stays stationary (due to lack of friction). Thus, the Reason correctly explains the Assertion.
(Reference: NCERT Class 11, Physics Part I, Chapter 4: Laws of Motion, Section 4.4 explicitly discusses this scenario: "If there were no friction, we would remain where we were, while the floor of the bus would simply slip forward under our feet..." [1]).

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