NET, IAS, State-SET (KSET, WBSET, MPSET, etc.), GATE, CUET, Olympiads etc.: Physics MCQs (Practice_Test 10 of 35)
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- The ratio of reverse-resistance to the forward-resistance of a good solid-state diode is about
- 10: 1
- 1: 10
- 1: 100
- 1: 1000
- For a BJT, the current amplification factor a = 0.9. This transistor is connected in CE configuration. When the base current changes by 0.4 mA, the change in collector current will be
- 36 mA
- 9 mA
- 4 mA
- 3.6 mA
- A CE amplifier has a voltage gain of 50, an input impedance of 1000 ohm, and an output impedance of 200 ohm. The power gain of the amplifier will be
- 24 dB
- 41 dB
- 250 dB
- 12500 dB
- The input signal given to a CE amplifier having a voltage gain of 150 is v1 = 2 cos (15t + 100) The corresponding output signal is
- 300 cos (15t + 190՚)
- 300 cos (15t + 90՚)
- 75 cos (15t + 10՚)
- 2 cos (15t + 190՚)
- Which one of the following logic gates does the given truth table represent? A B C 0 0 0 0 1 0 1 0 0 1 1 1
- NOT
- NOR
- OR
- AND
- The diagram of a logic circuit is given be-low: The output F of the circuit is represented by
- W (X + Y) .
- W (X. Y) .
- W + (X. Y)
- W + (X + Y)
- Assertion (A) : The angular momentum under a central force is constant.
- Reason (R) : Inverse square law of force is conservative.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true but R is NOT the correct explanation of A
- A is true but R is false
- A is false but R is true
- Assertion (A) : Lorenz transformations are linear transformations.
- Reason (R) : The velocity of light is invariant in all inertial frames.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true but R is NOT the correct explanation of A
- A is true but R is false
- A is false but R is true
- Assertion (A) : The upper surface of the wings of an aero plane is made convex and the lower surface is made concave.
- Reason (R) : The air currents at the top have a smaller velocity and thus less pressure at the bottom than at the top.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true but R is NOT the correct explanation of A
- A is true but R is false
- A is false but R is true
- Assertion (A) : All the rain drops hit the surface of the earth with the same constant velocity.
- Reason (R) : An object falling through a viscous medium eventually attains a terminal velocity.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true but R is NOT the correct explanation of A
- A is true but R is false
- A is false but R is true
- Assertion (A) : Experimental results indicate that the molar specific heat of hydrogen gas below 50 K is equal to R, where R is the universal gas constant.
- Reason (R) : A diatomic hydrogen molecule possesses three transnational and two rotational degrees of freedom.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true but R is NOT the correct explanation of A
- A is true but R is false
- A is false but R is true
- Assertion (A) : The pressure exerted by a gas is the same and independent of the finite size of the molecules.
- Reason (R) : Molecular collisions will invariably change the velocities of individual molecules but the number of molecules having any particular velocity will remain unaltered.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true but R is NOT the correct explanation of A
- A is true but R is false
- A is false but R is true
- Assertion (A) : With the help of a reversible engine it is possible to extract heat from a source and convert all of it into mechanical work.
- Reason (R) : Thermal energy and mechanical energy are different forms of energy.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true but R is NOT the correct explanation of A
- A is true but R is false
- A is false but R is true
- Assertion (A) : Photoelectric effect can take place only with an electron bound in the atom.
- Reason (R) : Electron is a fermions, whereas proton is a boson.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true but R is NOT the correct explanation of A
- A is true but R is false
- A is false but R is true