Question

A reactor operating at 1 MW is scrammed by instantaneous insertion of $5.00 of negative reactivity. Approximately how long does it take the power to drop to 1 milliwatt?

Answer 1

Answer:

time is 3333.33 min or 55.55 hr

Explanation:

given data

reactor operating = 1 MW

negative reactivity =  $5

power = 1 miliwatt

to find out

how long does it take

solution

we know here power coefficient that is

power coefficient = $\frac{10^{6} }{10^{6} }$

power coefficient = 1

so time required to reach power is

power =  reactivity × time / power coefficient + reactor operating

1 × $10^{-3}$ = -5 t / 1  +  1 × $10^{6}$

5t =  $10^{6}$ - $10^{-3}$

t = 199999.99 sec

so time is 3333.33 min or 55.55 hr