Ice forms on a refrigerator ice-box at the rate of (4 - 0...
Ice forms on a refrigerator ice-box at the rate of (4 - 06t)g per minute after t minutes. If initially there are 2g of ice in the box, find the mass of ice formed in 5 minutes
19.5
17.0
14.5
12.5
Correct answer is C
dmdt = 4 - 0.6t
∫dm = ∫(4 - 0.6t)dt
m = 4t−0.3t2+c, when t = 0, m = 2g
∴ c = 2
m = 4t−0.3t2+2, when t = 5 minutes
m = 4(5)−0.3(5)2+2=20−7.5+2
= 14.5