Question

Calculate the kinetic energy of a
30 g bullet fired at 200 m/s.

Answer 1

6 × 10⁵ J

Step-by-step explanation:

Kinetic Energy of a moving mass is defined as, half of the product of it's mass and the square of it's velocity.

`\boxed{ \mathsf{K.E. = (1)/(2) m( {v})^(2) }}`

• Mass of the bullet (m) = 30 g
• velocity (v) = 200 m/ s

`\implies\mathsf{K.E. = (1)/(2) * 30 * ( {200})^(2) }`

`\implies\mathsf{K.E. = 15 * 4 * {10}^(4) }`

`\implies\mathsf{K.E. = 60 * {10}^(4) }`

`\implies \underline{\mathsf{K.E. = 6 * {10}^(5) J }}`

Answer 2

Step 1: Identify the formula needed to solve this problem.

The formula for kinetic energy (KE) is:

KE = 1/2m~v^2

m = mass

v = velocity

Step 2: Make a list of the values given in the question.

mass (m) = 30 g

velocity (v) = 200 m/s

`(1)/(2) m {v}^(2) \\ (1)/(2) * 30 * {200}^(2) \\ 15 * 40000 \\ = 600000`