All Free Physics MCQs with Answers
Every Physics question in the bank, across all chapters, each with the correct answer and a written explanation. Free and unlimited, with no account needed.
13,934 questions · page 684 of 697
- A. NAND gate
- B. NOR gate
- C. OR gate
- D. XOR gate
Explanation: A NAND gate is a combination of AND and NOT gates. Option 'A' corresponds to the statement of the question.
Correct answer: NAND gate- A. Current gain
- B. Voltage gain
- C. Open-loop gain
- D. Closed-loop gain
Explanation: The correct answer is Voltage gain. It is defined as the ratio of the output voltage (V0) to the input voltage difference (Vin), which…
Correct answer: Voltage gain- A. Solar cell
- B. Photodiode
- C. Vacuum diode
- D. Light emitting diode
Explanation: The correct answer is the Light Emitting Diode (LED). LEDs are specifically designed to emit light when an electric current passes through…
Correct answer: Light emitting diode- A. Protons
- B. Electrons only
- C. Holes only
- D. Both electrons and holes
Explanation: In semiconductors, current is generated by the movement of charge carriers: electrons and holes.
Correct answer: Both electrons and holes- A. AC only
- B. DC only
- C. Both AC and DC
- D. None of them
Explanation: An operational amplifier is a very high gain voltage amplifier. It is used to amplify the signals by increasing its magnitude and can…
Correct answer: Both AC and DC- A. Holes
- B. Electrons
- C. Protons
- D. Positive ions
Explanation: Minority charge carriers are those charge-carrying units in a substance that are very few in quantity.
Correct answer: Electrons13667. In an unbiased P-N junction:
- A. The electric potential vanishes everywhere
- B. The electric field vanishes everywhere
- C. The diffusion current vanishes everywhere
- D. The diffusion and drift currents cancel each other
Explanation: A p-n junction is a boundary between two types of semiconductor materials, p-type and n-type.
Correct answer: The diffusion and drift currents cancel each other- A. Trivalent impurity
- B. Pentavalent impurity
- C. Pentavalent or trivalent impurities
- D. None of the above
Explanation: Intrinsic semiconductors, like silicon (Si) and germanium (Ge), have equal numbers of electrons and holes.
Correct answer: Pentavalent or trivalent impurities- A. N-type
- B. P-type
- C. Conductor
- D. All of the above
Explanation: In the p-type semiconductor, where there is a deficit of electrons, holes (positively charged vacancies) are the minority carriers.
Correct answer: P-type- A. Avatanche effect
- B. Break down of a diode
- C. Rectification
- D. Negative curent
Explanation: When a large current starts to flow in a reverse biased diode, it is known as the "avatanche effect." This happens when the reverse…
Correct answer: Avatanche effect- A. Emitter
- B. Base
- C. Collector
- D. Anyone can be heavily doped
Explanation: The heavily doped region is called the emitter. It plays a crucial role in the operation of the transistor by emitting majority charge…
Correct answer: Emitter- A. Capacitor
- B. ON switch
- C. Inductor
- D. OFF Switch
Explanation: When a PN junction is reverse biased, it acts like an insulator or an OFF switch.
Correct answer: OFF Switch- A. Gravitational forces and elastic forces
- B. Frictional force and propulsion of a motor
- C. electric force and tensioning string
- D. propulsion force of rocket and air resistence
Explanation: There are conservative and non-conservative forces. A conservative force is not path dependent, such as gravity and electrostatic forces.
Correct answer: Gravitational forces and elastic forces- A. All of these
- B. Zero
- C. Positive
- D. Negative
Explanation: The work done by the spring force can be positive, negative, or zero depending on the direction of motion and position of the particle.
Correct answer: All of these- A. E/2
- B. 2E
- C. E
- D. E/4
Explanation: EA = ½ kAxA2 Keeping force constant and using F= kx As kA = 2kB Then 2xA=xB Energy stored in B will be: EB= ½ (kA/2) (2xA)2 EB= ½ (2xA2…
Correct answer: 2E- A. 3:4
- B. 4:3
- C. 1:1
- D. None
Explanation: Factual. Gravitational potential for an equipotential surface (one that is at same height) is same for all masses. Hence ratio will be 1:1
Correct answer: 1:1- A. 98 J
- B. 49J
- C. 490 J
- D. 980 J
Explanation: The potential energy (PE) stored in an object is calculated as:PE = m × g × hwhere:m = mass of the object (10 kg)g = acceleration due to…
Correct answer: 490 J- A. 2.4 watts
- B. 120 watts
- C. 60 watts
- D. 300 watts
Explanation: The question is asking for the watt or power of the lamp. We know that P = IV and we are given that I = 5 amps and V = 12 volts.
Correct answer: 60 watts13679. If an amount of work △W is done by an agent in time interval △t, the power of that agency Will be:
- A. △W /△t
- B. △t / W△
- C. △t / △W
- D. △W + △t
Explanation: Thus power is defined as the rate of transfer of energy. In other words, we also define power.
Correct answer: △W /△t- A. power
- B. impulse
- C. couple
- D. Momentum
Explanation: Velocity=distance/time Force x velocity can also be written as force x distance or time force x distance = work done so the formula can be…
Correct answer: power