The speed of the cannon after firing is 1.2 m/s
This can be solved using the law of conservation of momentum.
From the law of conservation of momentum,
⇒ The momentum of the projectile is equal to the momentum of the cannon.
⇒ Where :
⇒ make V the subject of the equation
From the question,
⇒ Given:
⇒ Substitute these values into equation 2
Hence, The speed of the cannon after firing is 1.2 m/s
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