Electrostatic precipitator is used to control the pollution of (1) air (2) water (3) noise (4) thermal Answer: (1) An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. An electrostatic precipitator (ESP) or electrostatic … Read more
For a body moving with non-uniform velocity and uniform acceleration (1) Displacement – Time graph is linear (2) Displacement – Time graph is non-linear (3) Velocity – Time graph is non-linear (4) Velocity – Time graph is linear Answer: (2) Displacement-time graph is non-linear. Linear motion (also called a rectilinear motion) is moving along a straight … Read more
Longitudinal waves cannot travel through (1) Vacuum (2) Solid (3) Liquid (4) Gas Answer: (1) Longitudinal wave cannot travel through a vacuum because such wave requires a medium such as solid-liquid or air to travel through. They cannot travel through a vacuum or in space. Longitudinal waves, also known as “l-waves”, are waves that have the … Read more
Plants are dried up in winter due to frost because (1) Evaporation does not take place (2) Photosynthesis does not take place at such a low temperature (3) Respiration does not take place at low temperature (4) There is mechanical loss of tissues and drought condition prevails Answer: (4) Respiration does not rely on the sun … Read more
When pressure is increased the melting point of ice (1) increases (2) does not change (3) decreases (4) depends on the impurities in the ice Answer: (3) In this case, if we increase the pressure on the ice the ice-water system wants to try to lower it again. It can do that by making itself fit … Read more
Where are mesons found? (1) Cosmic rays (2) X-rays (3) Gamma rays (4) Laser beam Answer: (1) Mesons are not produced by radioactive decay but appear in nature only as short-lived products of very high-energy interactions in the matter, between particles made of quarks. In cosmic ray interactions, for example, such particles are ordinary protons and … Read more
A passenger standing in a bus is thrown outward when the bus takes a sudden turn. This happens due to (1) Outward pull on him (2) Inertia of motion (3) Change in momentum (4) Change in acceleration Answer: (2) This is the inertia of direction. It is the ability of the body to be in a … Read more
The hydraulic brakes used in automobiles is a direct application of : (1) Archimedes’ principle (2) Torricellian law (3) Bernoulli’s theorem (4) Pascal’s law Answer: (4) Pascal’s principle guarantees that the pressure is transmitted equally to all parts of the enclosed fluid system. This gives straight-line braking unless there is a fluid leak or something to … Read more
Which of the following occurred first? (1) Albert Einstein propounded the General Theory of Relativity (2) Max Planck unveiled the Quantum Theory (3) Guglielmo Marconi sent out the first wireless signals (4) Wright Brother’s successfully flew an aircraft Answer: (3) Guglielmo Marconi sent out the first wireless signals. In the early summer of 1895 and despite … Read more
An electron microscope gives higher magnification than an optical microscope, because : (1) it uses more powerful lenses (2) the velocity of electrons is smaller than that of visible light (3) the electrons have more energy than the light particles (4) the wavelength of electrons is smaller as compared to the wavelength of visible light Answer: (4) An … Read more