Question

A 20 kg curling stone is sliding is sliding in a positive direction at 4 m/s. A second curling stone is sliding at the same speed but in the opposite direction. What is the kinetic energy of the two stones?

Answer 1

The kinetic energy of the two curling stones is 320 J

Step-by-step explanation:

Given;

mass of the first curling stone, m₁ = 20 kg

velocity of the first curling stone, v₁ = 4 m/s

velocity of the second curling stone, v₂ = - 4m/s

assuming the second curling stone to have equal mass with the first stone = 20 kg

The kinetic energy of the first curling stone is given by;

K.E₁ = ¹/₂m₁v₁²

K.E₁ = ¹/₂(20)(4)²

K.E₁ = 160 J

The kinetic energy of the second stone is given by;

K.E₂ = ¹/₂m₂v₂²

K.E₂ = ¹/₂ (20) (-4)²

K.E₂ = 160 J

Thus, the kinetic energy of the two curling stones is given by;

K.E = K.E₁ + K.E₂

K.E = 160 J + 160 J

K.E = 320 J

Therefore, the kinetic energy of the two curling stones is 320 J