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All electromagnetic waves: are transverse waves; can travel through a vacuum ; travel at exactly the same speed in a vacuum, the speed of light, 300,000,000 m/s. The common designations are radio waves, microwaves, infrared (IR), visible light, ultraviolet (UV) light, X-rays and gamma-rays. ultraviolet rays lie beside violet of visible light and has a lesser frequency than visible light.

The resultant force acting on the man is given by w = mg - R Mg - mg = 0 The man feels weightless because the reaction, R is equal to the weight mg

V\(^2\) = U\(^2\) - 2gS 0 = 100\(^2\) - 2 x 10 x S = 10000 - 20S S = \(\frac{10000}{20}\) = 500m Which is independent of mass. The two bodies were acted upon by the same retarding force of gravity, which is independent of the mass of the body; therefore, both will be 500 m from the point of throw.

S = (1)/2gt2 S = (1)/2 x (10)/1 x 32 =5 x 9 = 45 m

Centripetal force, F = \( \frac{mv^2}{r} \) = \( \frac{2 \times 10^2}{4} \) = \( \frac{200}{4} \)= 50N

K e just before hitting the gound = P e at the maximum height (conservation of mechanical energy) K e = P e = mgh = 1.5 x 10 x 20 = 300 J

The liquid will rise up the capillary if it wets glass and falls below its wets glass and falls below its initial level if it does not wet glass

upthrust = weight in air - weight in liquid = 30 x 10 - 22 x 10 = 300 - 220 = 80 N

increase in volume, \(\Delta\)V = V x 3\(\alpha\) x \(\Delta \theta\) = 3 x 2.0 X 10\(^{-5}\) x 40 x (90 - 30) = 6 x 10\(^{-5}\) x 40 x 60 0.144 cm\(^3\) ∴ No correct option

Young modules = \( \frac{\text{Tensile stress}}{\text{Tensile strain}}\) = \( 1.1 \times 10^11 = \frac{7.7 \times 10^7}{\text{Tensile Strain}} \) ∴ Tensile strain = \( \frac{7.7 \times 10^7}{1.1 \times 10^{11}} \) = \( 7.0 \times 10^{7-11} = 7.0 \times 10^{-4} \)

A good thermometric liquid should not have a high thermal capacity so that the themperetue of the body being measured will not be affected ∴ II, III and IV are qualities of a good thermometer

Efficiency = \( \frac{\text{work output}}{\text{work input}} \times \frac{100}{1} \) = 40 = \( \frac{20 \times 10 }{x} \times \frac{100}{1} \) = 500J

Pressure in liquid is independent of cross sectional area of the container/ liquid ∴ the correct options are I & II

grease is more viscous than the rest of the liquids

Sound is the only mechanical wave among the rest which are electromagnetic waves.