Q20 of 48 Page 44

A bullet of mass m fired at 30° to the horizontal leaves the barrel of the gun with a velocity v. The bullet hits a soft target at a height h above the ground while it is moving downward and emerges out with half the kinetic energy it had before hitting the target. Which of the following statements are correct in respect of bullet after it emerges out of the target?

From law of conservation of energy,


⇒


⇒


⇒ …..(1)


it is given that while it is moving downward it emerges out with


half the kinetic energy


⇒


⇒ (substituting the value of v’ from eq (1))…..(2)


from eq (1) and (2)



⇒


∴ velocity of the bullet is more than half of its earlier velocity.


Hence, the bullet will move in a different parabolic path and internal


energy of the particle will increase.


option (b,d,f) is correct

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