Kinetic and potential energies

Define kinetic energy, its equation, its regular and SI base unit

Define kinetic energy, its equation, its regular and SI base unit

Energy due to the motion of an object with mass, J, Joule, kgm²s^-2

Ek = ½ mv²

Ek = kinetic energy, kgm²s^-2

m = mass, kg

v = velocity, ms^-1

What is something important to know about kinetic energy?

It is constant unless the velocity changes and velocity only changes during acceleration

What is work done equal to?

Work done = Transfer of ANY energy

How is the equation for kinetic energy derived?

v² = u² + 2as -u², /2a

s = v²-u² / 2a s = d, u = 0

d = v² / 2a, W = Fd, d = W/F

W/F = v² / 2a x F

W = F ( v² / 2a ) W = Ek, F = ma

Ek = ma ( v² / 2a )

Ek = ½ mv²

Define gravitational potential energy, its equation, its regular and SI base unit

Energy of an object due to it’s position in a gravitational field, J, Joule, kgm²s^-2

Ep = mgh

Ep = gravitational potential energy, kgm²s^-2

m = mass, kg

g = acceleration of free fall, 9.81ms^-2

h = height, m

How is the equation for gravitational potential energy derived?

W(ork done) = Fd, W(ork done) = Ep

F = W(eight), W(eight) =mg,

Ep =mgd, d = h

Ep = mgh

What is kinetic energy equal to, show this in equation form?

Gravitational potential energy

mgh = 1/2mv²

Describe energy exchange between Ep and Ek on a roller coaster with a diagram

1) Ep increases as the object rises

2) Ep is at its maximum

3) Ep transfers to Ek

4) Ep is at its minimum but has enough Ep to continue rising

5) Losing Ek and gaining Ep