A science centre uses two draining water reservoirs to model the main sequence stages of two stars.
The volume of water represents the usable hydrogen, the flow rate from the outlet represents the rate at which hydrogen is used, and the emptying time represents the main sequence lifetime.
Reservoir B starts with 20 times the volume of water in reservoir A but empties in 1500\displaystyle \frac{1}{500}5001 of the time taken by reservoir A.
Which statement about the outlet flow rates is correct?
The outlet flow rate of reservoir B is 110 000\frac{1}{10\,000}100001 of that of reservoir A.
The outlet flow rate of reservoir B is 10 00010\,00010000 times that of reservoir A.
The outlet flow rate of reservoir B is 252525 times that of reservoir A.
The outlet flow rate of reservoir B is 125\frac{1}{25}251 of that of reservoir A.
75 exam-style questions on Edexcel GCSE Physics 7.3 Stars, covering 7.3.1 Evolution of stars similar to the Sun, 7.3.2 Evolution of massive stars, and 7.3.3 Observing the Universe. Each one has a worked solution and a mark scheme showing where the marks go.