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Molecules of liquid are not stationary Brownian motion is an evidence of particle nature of matter matter is made up of molecules The molecules of matter are in constant motion

Efficiency = \(\frac{ma}{V.R}\) x \(\frac{100}{1}\) V.R = number of pulleys = 6 ma = \(\frac{\text{Load}}{\text{Effort}}\) = \(\frac{200}{50}\) = 4 Effiecieny = \(\frac{4}{6}\) × 100 = 66.67%

Resistor connected in a parallel have an equivalence given by \(\frac{1}{\text{Reff}}\) = \(\frac{1}{3}\) + \(\frac{1}{3}\) + \(\frac{1}{3}\) = \(\frac{1 + 1 + 1}{3}\) = \(\frac{3}{3}\) = 1 Reff = 1ω

Compressor is an instrument to supply air or other gas at increased pressure Refrigerator is an appliance to keep things cold Air blower is used to release air Air conditioner is used to remove heat and maintain a stable temperature in an occupied space

Isotopy is due to difference in mass number, what causes the difference is the difference in the number of neutrons present

Moment of a force is the product of a force and the perpendicular distance from the line of action of the force Moment = force \times distance = N \times m = Nm

Magnification = \(\frac{\text{Length of camera}}{\text{distance of object from pin hole}}\) m = \(\frac{12}{60}\) = 0.2 Also magnification m = \(\frac{\text{Height of image}}{\text{Height of object}}\) ∴ Height of image = m \times height of object = 0.2 \times 70 = 14cm

H = mcθ HP = HQ, θP = 2θ, mP = \(\frac{1}{2}\)mQ ∴ HP = mQCPθP, also HQ = mQCQθQ Since HP = HQ ∴ mPcPθP = mQcPθq Putting in the conditions \(\frac{1}{2}\)mQ × cP × 2θQ = mQ × θQ × cQ ∴ cP = cQ \(\frac{C_p}{C_Q}\)= \(\frac{1}{1}\) = 1:1

The relationship between the peak value and r.m.s value of electricity supply is given as V\(_{r.m.s}\) = \(\frac{V_o}{\sqrt{2}}\) where Vo = peak voltage ∴ Vo = V\(_{r.m.s}\) × √2 = 240 × √2 = 339.5v = 340v

A d.c generator is one in which its current is allowed to flow in one direction even through it may vary in value an a.c generator can only be made to produce a d.c by replacing the two slip rings with a single split ring or commutator.

For capacitance i n parallel, 2µF and 2µF are in parallel, their equivalence is 2µF and 2µF = 4µF The 4µF generated is now in series with the remaining 4µF. The net capacitance for series connection is \(\frac{1}{C}\) = \(\frac{1}{4}\) + \(\frac{1}{4}\) = 1 + \(\frac{1}{4}\) = \(\frac{2}{4}\) C = \(\frac{4}{2}\) = 2µF

Barometer is used to measure atmosphere pressure Thermometer is used to measure temperature Hydrometer is used to measure relative density of a liquid Manometer is used to measure the pressure of a gas

Power is the time rate of doing work i.e power = \(\frac{\text{energy}}{\text{time}}\) Since energy = mgH ∴ power = \(\frac{mgH}{t}\) = \(\frac{50 \times 10 \times 5}{t}\) = 500W

V = fλ λ = \(\frac{v}{f}\) = \(\frac{3 \times 10^8}{600 \times 10^3}\) = 500m = 5 × 102m N.B 600KHz Frequency = 600 × 103Hz

Scalar quantity is a quantity with only magnitude, it has no direction Tension, weight, impulse are vector quantities because they have direction. Mass is the only scalar quantity there