Changes

| style="height:20px; width:200px; text-align:center;" |A piano falls down light bulb is supplied a flight current of stairs625mA. In this fall 5.4kJ of The [[Potential Difference|potential difference]] across the terminals on the [[energyElectrical Bulb|light bulb]] is 96 [[Energy Transfer|transferredvolt]] from s. Calculate the [[Gravitational Potential Energy Store|gravitational potential energy storepower]] into of the [[Kinetic Energy StoreElectrical Bulb|kinetic energy storebulb]] of the piano. It take 0.80 seconds to reach the bottom of the stairs. Calculate the average '''power''' of this transfer correct to two [[Significant Figures|significant figures]].| style="height:20px; width:200px; text-align:center;" |A '[[weightElectrical Kettle|kettle]] lifter' lifts a 2000N is plugged into the [[weightMains Electricity|mains supply]] which operates at 230V. It receives a distance current of 1.2 [[metre]] from its original position. They do this in 0.70 [[second]]s9. 2Amps Calculate the [[power]] output of the '[[weight]] lifter' kettle correct to two [[Significant Figures|significant figures]].

W I = 5625mA = 0.4kJ = 5400J625A

t V = 0.80s96V

F I = 2000N9.2A

d V = 1.2m t = 0.70s230V

<math>P = \frac{W}{t}IV</math>

<math>P = I \frac{5400}{0.80}times V</math>

<math>P = 6750W0.625 \times 96</math>

<math>P \approx 6800W= 60W</math>

<math>W = \vec F \vec d</math> <math>W = \vec F \times \vec d</math> <math>W = 2000 \times 1.2</math> <math>W = 2400J</math> <math>P = \frac{W}{t}IV</math>

<math>P = I \frac{2400}{0.7}times V</math>

<math>P = 34289.57W2 \times 230</math>

<math>P \approx 3400W= 2116W</math>