Question

A canon ball of mass 500g is fired with a speed of 15m/s^-1. Find: (i) its kinetic energy and (ii) its momentum.

April 18, 2024

Answer

mass = 500 g = 0.5 kg

Speed = v = 15 m / s

(a) We know,

Kinetic energy = $1\over 2$ × mass × (velocity)²

Substituting the values in the equation we get,

Kinetic energy = $1\over 2$ × 0.5 × 15²

= $1\over 2$ × 0.5 × 225

= 56.25 J

(b) We know,

Momentum = mass × velocity

Substituting the values in the equation we get,

Momentum = 0.5 × 15 = 7.5 kgm/s

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