The sun is seen before the actual sunrise because of __________.
A biconvex lens has a radius of curvature of magnitude 20 cm. Which one of the following options describe best the image formed of an object of height 2 cm placed 30 cm from the lens?
Which of the following describes the energy changes takes place when a steam engine drives a generator which lights a lamp?
What is refractive index ?
How many times more intense is a 60 dB sound than a 30 dB sound?
The motion of a projectile follows a?
For one complete revolution θ =?
A body released inside the spacecraft does not fall relative to it, and it appears to be?
It is easier to roll a stone up a sloping road than to lift it vertical upwards because
Consider the following statement:
The principle of total internal reflection is
applicable to explain the
1. Formation of mirage in desert.
2. Formation of image in microscope.
3. Colour of evening sky.
4. Operation of optical fibres.
Which of the statement given above are correct?
The horizontal distance from the origin (x=O, y=O) to the point where the projectile returns (x = R, y=O) is called?
Let a thin capillary tube be replaced with another tube of insufficient length then, we find water
What is newton third law of motion ?
A perfect gas at 27°C is heated at constant pressure so as to double its volume. The increase in temperature of the gas will be ______.
Which instrument is used to measure sound under water ?
A body floats in water with 40% of its volume outside water. When the same body floats in an oil, 60% of its volume remains outside oil. The relative density of oil is
Which law is also called law of inertia ?
According to the Newton’s Universal law of gravitation, “Every body in the universe attracts every other body with a force which is?
Of the following properties of a wave, the one that is independent of the other is its
What does the term Dolby B or Dolby C printed on tape recorders and other sound systems refer to?
Artificial gravity is produced in a space-craft to?
A man is standing on a boat in still water. If he walks towards the shore, the boat will
What is unit of Astronomical distance ?
In parallel connection the current flows through each resistor is?
Consider the following statements:
A body weighs less at the equator than at the poles because:
1. earth rotates about its axis.
2. the ice cap at the poles increases gravitational pull.
3. equatorial diameter is greater than the polar diameter.
4. of some unknown facts.
Which of the statements given above is/are incorrect?
The distance between centre of the earth and moon is 384000 km. If the mass of the earth is 6 ´ 1024 kg and G = 6.66 ´ 10-11 Nm2/kg2. The speed of the moon is nearly
An unknown resistance R1 is connected in series with a resistance of 10Ω. This combination is connected to one gap of a metre bridge while a resistance R2 is connected in the other gap. The balance point is at 50 em. Now, when the 10 Ω resistance is removed the balance position shifts to 40 em. The value of R1 is (in ohm)
The unit of resistivity is?
If no external force acts on a system of bodies, the total linear momentum of the system of bodies remains constant. Which law states this ?