Do you know your formulae?

Unit 4 Formulae

 

Tell the person next to you…

·         All of the formulae from this unit

o    eg. "The formula that links Wd, F and d is…"

·         All of the quantities from this unit

o    eg. "Wd = Work done"

·         All of the units from this unit

o    eg. "The unit of Work Done is the Joule"

Answers

 

Formulae

 

·         Efficiency = Useful E_out/Total E_in x 100

or      Efficiency = Useful E_out/Total E_in

·         Wd = F x d

·         GPE = mgh

·         KE = ½mv²

·         P = E/t       or       P = Wd/t

·         Total E_in = Total E_out

(Principle of Conservation of Energy)

 

 

Quantities and Units

 

·         E_in = Energy input (J)

·         Wd = Work done (J)

·         GPE = Gravitational Potential Energy (J)

·         KE = Kinetic Energy (J)

·         F = force (N)

·         d = distance moved in the direction of the force (m)

·         m = mass (kg)

·         g = gravitational field strength (N/kg)

·         g_earth = 10N/kg

·         h = height (m)

·         v = velocity (m/s)

·         P = power (W)

·         t = time (s)