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 ▸Car 1 has a of mass 1000kg and is going at 20m/s. Car 2 has the same mass as Car 1 and is stationary. If they collide and travel together as one unit in the same direction as Car 1 was going, calculate the speed of the unit after the collision.
A person swims from a depth of 0.5m to 1.7m below the surface of the sea. Denisty Sea Water = 1030 kg/m^3. g=Gravitational Field Strength = 9.8 N/kg. Calculate the change in pressure on the swimmer and give the unit.
When a force is applied to a spring, the spring extends by 12cm. The spring has a spring constant of 25 N/m. Calculate the force applied to the string in N.
Calculate the momentum of a 5 tonne truck at 50km/h