answer
567000 J
formula
the formula for power is P = ΔE/Δt
rearrange for energy to get ΔE = PΔt
P is power in watts (W)
E is energy in joules (J)
t is time in seconds (s)
values
P = 315 W
t = 30 minutes = 30 * 60 = 1800 s
plug in values
ΔE = PΔt
ΔE = 315 * 1800
ΔE = 567000 J
