Light with an energy flux of 25×10⁴ Wm⁻² falls on a perfectly reflecting surface at normal incidence. If the surface area is 15 cm², the average force exerted on the surface is
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Two cities are 150 km apart. Electric power is sent from one city to another city through copper wires. The fall of potential per km is 8 volt and the average resistance per km is […]
The mean free path of molecules of a gas,(radius ‘r’) is inversely proportional to
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(a) r³ (b) r² (c) r (d) √r
Correct Answer:
r²
Explanation:
No explanation available. Be the first […]
Steam at 100⁰C is passed into 20 g of water at 10°C. When water acquires a temperature of 80°C, the mass of water present will be[Take specific heat of water=1 cal g⁻¹ °C⁻¹ and latent […]
If force(F), Velocity(V) and time(T) are taken as fundamental units, then the dimensions of mass are
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(a) FVT⁻¹ (b) FVT⁻² (c) FV⁻¹T⁻¹ (d) FV⁻¹T
Correct Answer:
FV⁻¹T
Explanation:
Using Newton’s Second law equation, […]
Two thin dielectric slabs of dielectric constants K₁ and K₂, (K₁ < K₂) are inserted between the plates of a parallel plate capacitor, as shown in the figure alongside. The variation of electric field E […]
Two identical long conducting wires AOB and COD are placed at right angle to each other, will one above other such that O is their common point for the two. The wires carry I₁ and […]
The resistance in the two arms of the meter bridge are 5Ω and RΩ, respectively. When the resistance R is shunted with an equal resistance, then the new balance point is at 1.6l₁. The resistance […]
The oscillation of a body on a smooth horizontal surface is represented by the equation, X=A cos(ωt) where, X=displacement at time t ω= frequency of oscillation Which one of the following graphs shows correctly the […]
The number of possible natural oscilations of air column in a pipe closed at one end of length 85 cm whose frequencied lie below 1250 Hz are (Velocity of sound = 340 m s⁻¹)
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