Q11 of 78 Page 13

Mark the correct alternative in the following:

The radius of a sphere is increasing at the rate of 0.2 cm/sec. The rate at which the volume of the sphere increases when radius is 15 cm, is


The volume of a sphere, of radius r, is defined by

– (1)


Given that r=15cm, , we have to calculate


Differentiating (1) with respect to t, we get



Substituting values, we get


More from this chapter

All 78 →
9

Mark the correct alternative in the following:

The coordinates of the point on the ellipse 16x2+9y2=400 where the ordinate decreases at the same rate at which the abscissa increase, are:


 10

Mark the correct alternative in the following:

The radius of the base of a cone is increasing at the rate of 3 cm/minute and the altitude is decreasing at the rate of 4 cm/minute. The rate of change of lateral surface when the radius = 7 cm and altitude 24 cm is:


 12

Mark the correct alternative in the following:

The volume of a sphere is increasing at 3 cm2/sec. The rate at which the radius increases when radius is 2 cm, is


 13

Mark the correct alternative in the following:

The distance moved by a particle travelling in a straight line in t seconds is given by s = 45t + 11t2 – t3. The time taken by the particle to come to rest is