Work and Power

Question 1

Whats the equation for work done?

Answer 1

WD = f x d

WD = Work Done (J)
f = Force (N)
d = Distance moved in the direction of force (m)

Question 2

Whats the equation for Gravitational Potential Energy

Answer 2

GPE = mgh

GPE = Gravitational Potential Energy (J)
m = Mass (kg)
g = GFS (N/kg) - 9.8 on earth
h = Height (m)

Question 3

Whats the equation for Kinetic Energy?

Answer 3

KE = 1/2mv^2

KE = Kinetic Energy
m = Mass (kg)
v = velocity (m/s)

Question 4

What is power?

Answer 4

Power is the rate of energy transfer

Question 5

What is the equation for Power (using power, time taken and work done)?

Answer 5

P = WD / t

P = Power (J)
WD = Work Done (J)
t = Time taken (s)

Question 6

Link between GPE and KE

Question 7

Unit of mass

Answer 7

Kilogram (Kg)

Question 8

Unit of energy

Answer 8

Joule (J)

Question 9

Unit of length

Answer 9

Metre (m)

Question 10

Unit of velocity/speed

Answer 10

Metre/ second (m/s)

Question 11

Unit of acceleration

Answer 11

Metre/ second^2(m/s^2)

Question 12

Unit of force

Answer 12

Newton (N)

Question 13

Unit of time

Answer 13

Second (s)

Question 14

Unit of electrical power

Answer 14

Watt (W)

Question 15

Is energy required to keep satellites in orbit?

Answer 15

No because it’s at a constant altitude

Question 16

What is energy?

Answer 16

The ability to do work

Question 17

What is The Law of Conservation of Energy?

Answer 17

Energy can’t be created or destroyed, it can only be transferred from one store to another