Related InterviewSolutions

• A ladder of length 20 feet rests against a smooth vertical wall. The lowerend, which is on a smooth horizontal floor is moving away from the wall at the rate of 4 feet/sec. If the lower end is 12 feet away from the wall, then the rate at which the upper end move, isA. `(16)/(3)" ft/sec"`B. `(-16)/(3)" ft/sec"`C. 3 ft/secD. `"-3" ft/sec"`
• The total cost `C(x)` of producing `x` items in a firm is given by `C(x)=0.0005x^3-0.002x^2+30x+6000` Find the marginal cost when `4` units are produced
• Oil is leaking at the rate of 16 mL/s from a vertically kept cylindrical drum containing oil. If the radius of the drum is 7 cm and its height is 60 cm, find the rate at which the level of the oil is changing when the oil level is 18 cm
• A ladder is inclined to a wall making an angle of 30° with it. A man is ascending the ladder at the rate of 3 m/sec. How fast is he approaching the wall ?
• A square plate is contracting at the uniform rate of `2 cm^(2)//sec`. If side fo the square is 16 cm long, then the rate of decrease of its perimeter isA. `(1)/(2) cm//sec.`B. `(-1)/(2) cm//sec.`C. `(1)/(4) cm//sec`D. `(-1)/(4) cm//sec`
• A man of height 160 cm walks at a rate of 1.1` m/sec from a lamp post which 6m high. Find the rate at which the length of his shadow increases when he is 1m away from the lamp post.
• The side of a square in increasing at the rate of 0.2 cm/sec. Find therate of increase of the perimeter of the square.
• If the radius of a circle is 2 cm and is increasing at the rate of 0.5 cm/sec., then the rate of increase of its area isA. `pi cm^(2)//sec`B. `2pi cm^(2)//sec`C. `3pi cm^(2)//sec`D. `4pi cm^(2)//sec`
• A bullet is shot horizontally and its distance s cms at time `t` sec is given by `s=1200t-15t^(2)` then the distance covered with which the bullet is shot when it comes to the rest isA. 48000 cms.B. 24000 cmsC. 4800 cmsD. 2400 cms
• A particle moves along the curve `6y = x^3 + 2`.Find the points on the curve at whichy-co-ordinate is changing 8 times as fast as thex-co-ordinate.