Question

A ball of mass 200 g rolls along the ground at a speed of 5.2 m/s. Calculate the kinetic energy of the ball. Give your answer to two significant figures.

Answer 1

The right answer is "2.7 J"

Answer explanation:

Remember to convert grams to kilograms first by dividing by 1000.

Kinetic energy

= 1/2 × mass × speed2

= 1/2 × 0.2 kg × (5.2 m/s)^2

= 2.7 J (to 2 sig. fig.)

Hope it helps ✨✨

Answer 2

Kinetic Energy = 2.7J

Step-by-step explanation:

Conversion :

200g = 0.2kg

Kinetic Energy = ½ × mass × (velocity)²

Kinetic Energy = ½ × 0.2kg × (5.2m/s²)

Kinetic energy = ½ × 0.2kg × 27.04m²/s²

Kinetic Energy = 2.7J