List of top Physics Questions

The COP of a heat pump is 40% of a reversible heat pump. The operating temperatures limits are \(2°C\) and \(25°C\). If 2.5 kW of heat is pumped by the heat pump in a room to be heated, then the power input to the heat pump is:
The dispersion relation for electromagnetic waves travelling in a plasma is given by \(ω^2 = c^2k^2-ω^2_ρ\), where c and \(ω_ρ\), are constants. In this plasma, group velocity will be
The temperature distribution along a fin with insulated tip is: w
The relative magnitude of \(\overrightarrow H\) in a plane wave is 1 \(Am^{-1}\). What will be the magnitude of \(\overrightarrow E\) for a plane wave in free space?
Match List I with List II
List IList II
A.Temperature correction (Ct)I.\(\frac{(P_m-P_o)L}{AE}\)
B.Puel correction (Cp)II.\(\frac{h^2}{2L}\)
C.Slope correction (Ch)III.\(\alpha(T_m-T_o)L\)
D.Sag correction (Cs)IV.\(\frac{LW^2}{24n^2P_m^2}\)
Choose the correct answer from the options given below :
From the evaporator of a vapour compression refrigerator the refrigerant leaves at 205 KJ/kg and leaves condensor at 75 KJ/kg. The cooling load in kW for supply of refrigerant per kg per second is:
A band brake having a bandwidth of 90 mm, drum diameter of 300 mm, coefficient of friction of 0.3 and an angle of wrap of \(270\degree\) is required to create a friction torque of 1000 Nm. The maximum tension (in kN) developed in the band is:
The following logic circuit represents
Logic Circuit
Head lost due to friction is 7 m in a pipe flow. The total head at the inlet of the pipe to be maintained for maximum power transmission through the pipe is:
Match List I with List II
LIST I (Oscillator and Amplifier)LIST II (Characteristics)
AWien-bridge oscillatorILow output impedance
BVoltage-shunt feedback amplifierIIRF frequency range
CCrystal OscillatorIIIAudio frequency range
DCurrent-shunt feedback amplifierIVHigh output impedance
Choose the correct answer from the options given below:
If the power and current gains of a transistor amplifier are 16500 and 100 respectively, then voltage gain is___
Given below are two statements:
Statements-I: Compton effect can be explained on the basis of wave nature of light.
Statements-II: Diffraction pattern of light can be explained on the basis of particle nature of light.
In the light of the above statements, choose the correct answer from the options given below.
The purpose of a coupling capacitor in a transistor amplifier is to___
The change in entropy (△S) for a reversible adiabatic process is
Dark Current in semi-conductor photo-diode is___
Given below are two statements :
Statements-I : Important characteristic of electromagnetic wave is that it can transport energy from one point to another point.
Statements-II : The direction of electromagnetic wave at a given point is the direction in which energy is being transmitted.
In the light of the above statements, choose the correct answer from the options given below.
Match List I with List II
LIST I (Type of Test)LIST II Quantities to be measured)
AOpen circuit testICopper loss and iron loss
BShort circuit testIITotal losses
CSumpner's testIIIIron test
DLoad testIVCopper losses
Choose the correct answer from the options given below:
A hollow cylindrical pipe is insulated using asbestos insulation (k = 0.15 W/mK). If outside heat transfer coefficient is 75 W/m2K, then critical radius of insulation is:
What will be the range of input voltage \(V_i\) in which the Zener diode shown in the figure below, conducts?
Zener Diode
Given below are two statements :
Statement-l : We can join two P-N junctions back-to-back to form a transistor
Statement-II In a transistor the emitter base junction is forward biased while base collector junction is reverse biased.
In the light of the above statements, choose the correct answer from the options given below.
The stream function for a two-dimensional flow is given by y=2xy. the velocity at (2.2) is.
Match List I with List II
LIST I
 		 LIST II
 
A. Uniform flow I.Flow through a water supply pipe.
B.Laminar flowII.Flow through a straight tube of uniform diameter and uniform roughness 
C.Turbulent flowIII. Flow above the drain hole of wash basin
D.Irrotational flow IV.Flow of blood in veins and Arteries

Choose the most appropriate answer from the options given below:

The function of oil in transformer is
A solenoid of length 30 cm is wound uniformly with 3000 turns of wire. The wire carries a current of 10 A. What is the value of B on the axis within the solenoid? [μ0=4лx10-7 T m/A]
The relative permittivity of distilled water is 81. What is the velocity of light in the distilled water?