This question is about laser-propulsion transmitter calculations.
Write down the equation which links energy (EEE), power (PPP), and time (ttt).
A ground-based laser-propulsion transmitter has a continuous power output of 480 MW480\text{ MW}480 MW. Calculate the total energy output of this transmitter if it beams continuously for 7500 s. Give your answer in Joules (J\text{J}J) in standard form.
Due to essential recalibration and cooling cycles, the laser transmitter is not active every day of the year. Over a standard year (where 1 year=365 days1\text{ year} = 365\text{ days}1 year=365 days), the transmitter was active for 78% of the year. Calculate the number of days during that year that the laser transmitter was active.
44 exam-style questions on AQA GCSE Physics 1.1 Energy changes in a system, and the ways energy is stored before and after such changes, covering 1.1.1 Energy stores and systems, 1.1.2 Changes in energy, 1.1.3 Energy changes in systems, and 1.1.4 Power. Each one has a worked solution and a mark scheme showing where the marks go.