- #1

utkarshakash

Gold Member

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## Homework Statement

A cannon of mass M starts sliding freely down a smooth inclined plane at an angle α to the horizontal. After the cannon covered the distance l, a shot was fired, the shell leaving the cannon in the horizontal direction with a momentum

**p**. As a consequence, the cannon stopped. Assuming the mass of the shell to be negligible, as compared to that of the cannon, determine the duration of the shot.

## Homework Equations

Kinematics Equations

Conservation of Momentum

## The Attempt at a Solution

Acceleration of cannon along incline = [itex]gsinα[/itex]

Distance covered = l

Initial Velocity = 0

So final velocity of the cannon (v) = [itex]\sqrt{2glsinα}[/itex]

If I take X-axis along the incline and Y-axis perpendicular to it

[itex]\vec{p}_{i}=Mvcosα[/itex]

[itex]\vec{p}_{f}=0[/itex] (Since cannon stops)

Since I have to find duration of shot so that means I have to find the time interval during which the momentum of the cannon changed. Am I right with this assumption or does that means something else? If I'm right then how do I find it?