the radius of curvature of a thin plano-convex lens is 10 cm(of curved surface) and the refractive index is 1.5. If the plane surface is silvered, then it behaves like a concave mirror of focal length?

Anonymous User Physics IIT 15 Sep, 2018 795 views

A school has four sections of chemistry in class XII having40, 35, 45 and 42 students. The mean marks obtained inChemistry test are 50, 60, 55 and 45 respectively for the four sections, the over all average of marks per students is?

Anonymous User Maths IIT 13 Sep, 2018 1857 views

The radius of curvature of a thin plano-convex lens is 10 cm(of curved surface) and the refractive index is 1.5. If theplane surface is silvered, then it behaves like a concavemirror of focal length?

Anonymous User Physics IIT 12 Sep, 2018 2387 views

A ball is thrown upward with initial velocity v0 = 15.0 m/s atan angle of 30° with the horizontal. The thrower stands nearthe top of a long hill which slopes downward at an angle of20°. When does the ball strike the slope ?

Anonymous User IIT Physics 12 Sep, 2018 397 views

A small mass slides down a fixed inclined plane of inclination with the horizontal.

The coefficient of friction is where x is the distance through which the mass slides down
and is a constant. Then the speed is maximum after the mass covers a distance of?

Anonymous User Physics IIT 11 Sep, 2018 876 views

In a geometric progression consisting of positive terms, each term equals the sum of the next two terms. Then the common ratio of this progression is equals

Devendra Yadav Maths IIT 06 Sep, 2018 136 views

The first two terms of a geometric progression add up to 12. The sum of the third and the fourth terms is 48. If the terms of the geometric progression are alternately positive and negative, then the first term is?

Rajat Sharma IIT Maths 04 Sep, 2018 188 views

A student is to answer 10 out of 13 questions in an examination such that he must choose at least 4 from the first five questions. The number of choices available to him is?

Anonymous User IIT JEE MAIN Maths 02 Sep, 2018 176 views

The reason for double helical structure of DNA is operation of?

Preeti Rai IIT Chemistry 30 Aug, 2018 124 views

Which of the following liquid pairs shows a positive deviation from Raoult’s law?

(a) Water ­ hydrochloric acid

(b) Benzene ­ methanol

(c) Water ­ nitric acid

(d) Acetone ­ chloroform.

Devendra Yadav IIT Chemistry 27 Aug, 2018 254 views

A mass m hangs with the help of a string wrapped around a pulley on a frictionless bearing. The pulley has mass m and radius R. Assuming pulley to be a perfect uniform circular disc, the acceleration of the mass m, if the string does not slip on the pulley, is?

Anonymous User Physics IIT 23 Aug, 2018 912 views

A diatomic ideal gas is used in a Carnot engine as the working substance. If during the adiabatic expansion part of the cycle the volume of the gas increases from V to 32V, the efficiency of the engine is?

Anonymous User Physics IIT 23 Aug, 2018 176 views

The intensity of gamma radiation from a given source is I. On passing through 36 mm of lead, it is reduced to I/8. The thickness of lead which will reduce the intensity to I/2 will be?

Anonymous User Chemistry IIT 22 Aug, 2018 159 views

A radioactive sample at any instant has its disintegration rate 5000 disintegrations per minute.After 5 minutes, the rate is 1250 disintegrations per minute. Then, the decay constant (per minute) is?

Anonymous User Chemistry IIT 21 Aug, 2018 2122 views

A car, starting from rest, accelerates at the rate f through a distance s, then continues at constant speed for time t and then decelerates at the rate f/2 to come to rest. If the total distance traversed
is 15 s, then what will be the value of s?

Anonymous User Physics IIT 21 Aug, 2018 222 views

Two particles, 1 and 2, move with constant velocities v1 and v2. At the initial moment their radius vectors are equal to r1 and r2.How must these four vectors be interrelated for the particles to collide?

Anonymous User IIT Physics 15 Aug, 2018 144 views

Consider a car moving on a straight road with a speed of 100 m/s. The distance at which car can be stopped is? Anonymous User IIT Physics 15 Aug, 2018 409 views

A light string passing over a smooth light pulley connects two blocks of masses m1 and m2 (vertically). If the acceleration of the system is g/8, then the ratio of the masses is?

Anonymous User Physics IIT 14 Aug, 2018 401 views

A lift is moving down with acceleration a. A man in the lift drops a ball inside the lift. The acceleration of the ball as observed by the man in the lift and a man standing stationary on the ground are respectively?

Anonymous User Physics IIT 13 Aug, 2018 486 views