Current has a direction. By convention, current is in the direction that ___.
A uniform wire of resistance R is uniformly compressed along its length, until its radius becomes n times the original radius. New resistance of the wire becomes
Which instrument is used to determine the intensity of colours ?
A planet is moving around the Sun in a circular orbit of circumference C. The work done on the planet by the gravitational force F of the Sun is
Kicked or thrown balls, jumping animals, object thrown from a window, a missile shot from a gun, a bomb released from a bomber plane, etc are all example of?
Three liquids of equal masses are taken in three identical cubical vessels A, B and C. Their densities are PA, PB and PC respectively. But PA < PB < PC. The force exerted by the liquid on the base of the cubical vessel is ______
Which law states, "The rate of loss of heat by a body is directly proportional to the difference in temperature between the body and the surroundings."
If a body is taken from a pole to the equator its distance from the center of the earth will?
If an electric circuit could be compared to a water circuit at a water park, then the current would be analogous to the ____.
Which instrument is used to measure pressure of gases ?
The number of coulombs of charges that passes any section of the conductors in one second is called?
The unit of temperature coefficient of resistivity is?
Force of attraction between the molecules of different substances is called
The focal length of a plano convex lens is 'f' and its refractive index is 1.5. It is kept over a plane glass plate with its curved surface touching the glass plate. The gap between the lens and the glass plate is filled by a liquid. As a result, the effective focal length of the combination becomes 2f. Then the refractive index of the liquid is ______.
The unit of resistivity is?
A simple pendulum is suspended from the ceiling of a lift. When the lift is at rest its time period is T. With what acceleration should the lift be accelerated upwards in order to reduce its period to T /2? (g is acceleration due to gravity).
What is newton third law of motion ?
If the radius of the earth were to shrink and its mass were to remain the same, the acceleration due to gravity on the surface of the earth with?
Consider the following statements:
1. Light of longer wavelength is scattered much more than the light of shorter wavelength.
2. The speed of visible light in water is 0.95 times the speed in vacuum.
3. Radio waves are produced by rapidly oscillating electrical currents.
4. To detect the overspeeding of vehicles, police use the Doppler effect to reflected short radio waves.Which of these statements are correct?
What is escape velocity ?
Intensity of sound at a point is ____ its distance from the source.
Electrical conductors contains?
A body weighs 50 grams in air and 40 grams in water. How much would it weigh in a liquid of specific gravity 1.5?
The absorption of ink by blotting paper involves
Mica is used in electrical appliances such as electric iron because mica is
A missile is launched with a velocity less than the escape velocity. The sum of its kinetic and potential energy is
The force of gravity on a body varies slightly from place to place on the earth for two reason. (i) shape of earth and (ii) ?
A closed organ pipe and an open organ pipe of same length produce 2 beats/second while vibrating in their fundamental modes. The length of the open organ pipe is halved and that of closed pipe is doubled. Then, the number of beats produced per second while vibrating in the fundamental mode is ______.
Consider the following statements and select the correct code.
Assertion (A): In our houses, the current in A.C. electricity line changes direction 60 times per second.
Reason (R): The frequency of alternating voltage supplied is 50 Hz.