Kinetic energy and Gravitational potential energy(5.3)

Question 1

What is Kinetic energy?

Answer 1

Kinetic energy is the energy associated with an object as a result of its motion.

Question 2

What is Gravitational potential energy?

Answer 2

Gravitational potential energy is the capacity for doing work as a result of an object’s position in a gravitational field.

Question 3

What is the equation for kinetic energy?

Answer 3

Kinetic energy(J / Nm) = 0.5 x mass(Kg) x velocity^2(ms^-1)

Question 4

What is the equation for Gravitational potential energy

Answer 4

Gravitational potential energy(J / Nm) = mass(Kg) x gravitational field strength(NKg^-1) x height(m)

Question 5

How do you derive the gravitational field strength?

Answer 5

Elastic potential energy = Work done = force x distance moved
~substitute the appropriate values~
Elastic potential energy = weight x height
~substitute the equation for weight~
Elastic potential energy = mass x gravitational field strength x height

Question 6

How do you derive the Kinetic energy equation?

Answer 6

~The distance ‘s’ traveled by the object can be determined from the equation of motion v^2 = u^2 x 2as.~
s = (v^2 - u^2) / 2a
~since the initial velocity of a falling object will be zero u = 0~
s = v^2 / 2a
~The work done by the force is entirely transferred to the Kinetic energy of the object.~
Work done = Kinetic energy = Fs
~The force is given by F = ma~
Kinetic energy = (ma) x v^2 / 2a
~acceleration cancels out~
Kinetic energy = 0.5 x m x v^2