Words of length 10 are formed using the letters, A, B, C, D, E, F, G, H, I, J. Let x be the number of such words where no letter is repeated ; and let y be the number of such words where exactly one letter is repeated twice and no other letter is repeated. Then, y/9x=?

A stationary source emits sound of frequency f0 = 492 Hz. The sound is reflected by a large car approaching the source with a speed of 2 m/s . The reflected signal is received by the soruce and superposed with the original. What will be the beat frequency of the resulting signal in Hz? (Given that the speed of sound in air is 330 m/s and the car reflects the sound at the frequency it has received).

Enzymes and name of any enzyme of our digestive system and its function.

Of the following natural phenomena, tell which one known in Sanskrit as 'deer's thirst'? A. Rainbow B. Earthshine C. Halo D. Mirag

Why It takes much longer to cook food in the hills than in the plains?

Why Stars twinkle?

Suitable impurities are added to a semiconductor depending on its use. This is done in order to

On a clean glass plate a drop of water spreads to form a thin layer whereas a drop of mercury remains almost spherical because

Sound of frequency below 20 Hz is called ?

Why RADAR is used ?

Materials for rain-proof coats and tents owe their water-proof properties to A. surface tension B. viscosity C. specific gravity D. elasticity

Point A is at a lower electrical potential than point B. An electron between them on the line joining them will A. move towards A B. move towards B C. move at right angles to the line joining A and B D. remain at rest

Why On a rainy day, small oil films on water show brilliant colors. This is due to

Lux is the SI unit of A. intensity of illumination B. luminous efficiency C. luminous flux D. luminous intensity Lux is the SI unit of A. intensity of illumination B. luminous efficiency C. luminous flux D. luminous intensity

Find the maximum velocity for the overturn of a car moving on a circular track of radius 100 m. The co-efficient of friction between the road and tyre is 0.2

Why It is more difficult to walk on a sandy road than on a concrete road ?

how much amount of Magnetism at the centre of a bar magnet ?

Why Rectifiers are used ?

Which one is the scalar quantity A. force B. pressure C. velocity D. acceleration

If two bodies of different masses, initially at rest, are acted upon by the same force for the same time, then the both bodies acquire the same

Why Metals are good conductors of electricity?

why Planets do not twinkle ?

Pa(Pascal) is the unit for ?

Why Stars appears to move from east to west?

How much Time Light takes to reachs us from from the Sun

what causes of Mirage?

what is unit of light Year?

in which unit Nuclear sizes are expressed ?

the level of the liquid in the two vessels are at the same height

How Radiocarbon is produced in the atmosphere.

An external pressure P is applied on a cube at 0°C so that it is equally compressed from all sides. K is the bulk modulus of the material of the cube and

When a current of 5 mA is passed through a galvanometer having a coil of resistance 15Ω, it shows full scale deflection. The value of the resistance to be put in series with the galvanometer to convert it into a voltmeter of range 0 – 10V is?

Mrs. Rodger got a weekly raise of $145. If she gets paid every other week, write an integer describing how the raise will affect her paycheck.

A man grows into a giant such that his linear dimensions increase by a factor of 9. Assuming that his density remains same, the stress in the leg will change by a factor of?

For three events A, B and C, P(Exactly one of A or B occurs) = P(Exactly one of B or C occurs) = P (Exactly one of C or A occurs) = 1/ 4 and P(All the three events occur simultaneously) = 1 /16 . Then the probability that at least one of the events occurs, is?

3-Methyl-pent-2-ene on reaction with HBr in presence of peroxide forms an addition product. The number of possible stereoisomers for the product is ?

The products obtained when chlorine gas reacts with cold and dilute aqueous NaOH are:

The formation of which of the following polymers involves hydrolysis reaction?

The most abundant elements by mass in the body of a healthy human adult are: Oxygen (61.4%); Carbon (22.9%), Hydrogen (10.0%); and Nitrogen (2.6%). The weight which a 75 kg person would gain if all H atoms are replaced by 2H atoms is?

A capacitance of 2 µF is required in an electrical circuit across a potential difference of 1.0 kV. A large number of 1 µF capacitors are available which can withstand a potential difference of not more than 300 V. The minimum number of capacitors required to achieve this is?

A time dependent force F = 6t acts on a particle of mass 1 kg. If the particle starts from rest, the work done by the force during the first 1 sec. will be?

In a Young’s double slit experiment, slits are separated by 0.5 mm, and the screen is placed 150 cm away. A beam of light consisting of two wavelengths, 650 nm and 520 nm, is used to obtain interference fringes on the screen. The least distance from the common central maximum to the point where the bright fringes due to both the wavelengths coincide is

A copper ball of mass 100 gm is at a temperature T. It is dropped in a copper calorimeter of mass 100 gm, filled with 170 gm of water at room temperature. Subsequently, the temperature of the system is found to be 75 C. T is given by: (Given : room temperature = 30 C, specific heat of copper = 0.1 cal/gm C)

If two different numbers are taken from the set {0, 1, 2, 3, …, 10}; then the probability that their sum as well as absolute difference are both multiple of 4, is:

For three events A, B and C, P(Exactly one of A or B occurs) = P(Exactly one of B or C occurs) = P (Exactly one of C or A occurs) = 1 /4 and P(All the three events occur simultaneously) = 1/ 16 . Then the probability that at least one of the events occurs, is:

Two reactions R1 and R2 have identical pre exponential factors. Activation energy of R1 exceeds that of R2 by 10kj /mol. if k1 and k2 are rate constants R1 and R2 respectively at 300 K, then In (K2/K1) is equal to? Given (R=8.314 J/mol K)

A metal crystallise is a face entered cubic structure. if the edge length of its unit cell is ‘a’, the closest approach between two atom in metallic crystal will be?

The fallowing observations were taken for determine surface tension T of water by capillary method: diameter of capillary, D = 1.25 * 10^-2 m rise of water, h = 1.45* 10^-2m Using g = 9.80 m/s^2 and the simplified relation T = rhg/2*10^3 N/m, the possible error in surface tension is closest to?

A resistance of 10^3 , a capacitance of 10^-6 F and an inductance of 2 Henry are connected in series with a source of 200 sin (1000 t) volt. Which of the following are correct?

A car is standing 200 m behind a truck which is also at rest.The two start moving at the same instant but the different forward accelerations.The truck has acceleration 2 m/s^2 and the car has acceleration 4m/s^2. The car will catch up with bus after a time?