A 6.0W bulb is connected to a source of 480J of energy. Assuming the system is 100% efficient, and the bulb runs at full power, how long can it stay lit?
- Bulb power = 6.0W - Energy provided = 480J - Use equation P = E / t (Power = energy/time) where power is in watts, energy is in joules, and time is in seconds - Rearrange the equation to give t = E / P (time = energy/power) to find the time in seconds - Plug in the values to give t = 480/6 = 80 - Therefore time = 80 seconds.
LW
Related Physics GCSE answers
All answers ▸How do you calculate the specific heat capacity of a substance?
Using newtons laws explain how a falling object can reach terminal velocity (6)
Explain the difference between speed and velocity.
A 15kg cannonball and a 1kg football are dropped to the ground from a height of 10 metres. Calculate the speed of the cannonball and of the football just before they hit the ground (you may ignore air resistance).