Question

How much kinetic energy does a 7.2-kg dog need to make a vertical jump of 1.2 m? (The acceleration due to gravity is 9.8 m/s2.)

Answer 1

How much kinetic energy does a 7.2-kg dog need to make a vertical jump of 1.2 m?
Answer:

85 Joule (approx)

Explanation:

Potential energy at highest point

P.E = mgh = 7.2 kg × 9.8 m/s2×1.2 m≈85 Joule

This is the kinetic energy required for dog to jump a height of 1.2 m.

hope this helps!

Answer 2

Answer:

Kinetic energy of dog is 84.67 Joules

Explanation:

Given that,

Mass of the dog, m = 7.2 kg

We have to find the kinetic energy does a 7.2-kg dog need to make a vertical jump of 1.2 m. We know that the energy of a system remains conversed. At highest point there is only potential energy. So, while taking a vertical jump the potential energy gets converted to potential energy.

So, $E_k=mgh$

here, h = 1.2 m

$E_k=7.2\times 9.8\times 1.2$

$E_k=84.67\ Joules$

Hence, the kinetic energy needed to make a vertical jump is 84.67 Joules.