Differential EquationHard

Question

A spherical balloon is filled with 4500π cubicmeters of helium gas. If a leak in the balloon causes the gas to escape at the rate of 72π cubic meters per minute, then the rate (in meters perminute) at which the radius of the balloon decreases 49 minutes after the leakage began is :

Options

A.9/2
B.9/7
C.7/9
D.2/9

Solution


Initially r = 4500 π, r = r0 
r0 = 15m
Now ......(i)
= - 18 t + C
At time t = 49 min      r = 9 m
from eq. (i)
= - 2/9
(Negative sign shows decrement in radii)

Create a free account to view solution

View Solution Free
Topic: Differential Equation·Practice all Differential Equation questions

More Differential Equation Questions

The slope of a curve at any point is the reciprocal of twice the ordinate at the point and it passes through the point (...The solution of the differential equation (1 + y2) + = 0, is...The solution of = sin (x + y) + cos (x + y) is-...The order of the differential equation whose general solution is given by y = (C1 + C2) cos (x + C3) - C4ex+c5 where C1,...If a2 + b2 + c2 = - 2 and f(x) = then f(x) is a polynomial of degree...