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Karnataka Board PUCPUC Science Class 11

Find the Average Velocity of a Projectile Between the Instants It Crosses Half the Maximum Height. It is Projected with a Speed U at an Angle θ with the Horizontal.

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Question

Find the average velocity of a projectile between the instants it crosses half the maximum height. It is projected with a speed u at an angle θ with the horizontal.

 
Short/Brief Note
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Solution

Given:
Initial velocity of the projectile = u
Angle of projection = θ
To find: Average velocity of the projectile
Average velocity 

\[= \frac{ \text{ Change in displacement }}{\text{ Time } }\]
Consider the projectile motion in the figure given below.

By the symmetry of figure, it can be said that the line joining points A and B is horizontal.
So, there will be no effect of the vertical component of velocity of the projectile during displacement AB.
We know that the projectile moves at a constant velocity u cos θ in horizontal direction.
Hence, the average velocity of the projectile is u cos θ.

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Chapter 3: Rest and Motion: Kinematics - Exercise [Page 53]

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HC Verma Concepts of Physics Volume 1 and 2 [English]
Chapter 3 Rest and Motion: Kinematics
Exercise | Q 39 | Page 53

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