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Karnataka Board PUCPUC Science Class 11

Read the statement below carefully and state, with reason and example, if it is true or false: A particle in one-dimensional motion with positive value of acceleration must be speeding up.

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Question

Read the statement below carefully and state, with reason and example, if it is true or false:

A particle in one-dimensional motion with positive value of acceleration must be speeding up.

Options

  • True 

  • False

MCQ
True or False
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Solution

This statement is False.

Explanation:

A particle in one-dimensional motion with a positive value of acceleration is not necessarily speeding up. The particle will speed up only if its velocity and acceleration are in the same direction. If the velocity and acceleration are in opposite directions (for example, if the particle is moving in the negative direction while the acceleration is positive), the particle is actually slowing down.

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Chapter 2: Motion in a Straight Line - Exercise [Page 24]

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NCERT Physics Part 1 and 2 [English] Class 11
Chapter 2 Motion in a Straight Line
Exercise | Q 2.7 (d) | Page 24

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