A toy plane has a mass of 2.5 kg and is 18 m above the ground. It is moving at 4.5 m/s. How much mechanical energy does the toy plane have? 
416 J, 475 J, 466 J, 491 J

Solution:

Given mass of toy plane is 2.5 kg at 18 m above the ground.

Its velocity is 4.5 m/s.

We know that the total amount of mechanical energy is merely the sum of the potential energy and the kinetic energy.

We know potential energy ,

P= (mass)(gravity)(height)

= 2.5(9.8)(18)

= 441 J

Kinetic energy K = 1/2(mass)(velocity)²

= 1/2(2.5)(4.5)²

= 25.31 J

Mechanical energy = Potential energy + Kinetic energy

= 450 + 25.31

= 466.31 J

Hence, 466J approx is the required answer.

---

A toy plane has a mass of 2.5 kg and is 18 m above the ground. It is moving at 4.5 m/s. How much mechanical energy does the toy plane have?

Summary:

A toy plane has a mass of 2.5 kg and is 18 m above the ground. It is moving at 4.5 m/s. The toy plane has a mechanical energy of 466J approx.