Physics holds 894 questions with answers, free to read and with no account needed. They are grouped into 1 category: Physics.
Attempt each question before revealing the answer, and keep a note of the ones you get wrong — those are the topics worth reading about properly. If an answer looks wrong, there is a link to report it on every question.
Answer: D. copper
Copper possesses exceptionally high electrical conductivity among accessible industrial metals. It offers low electrical resistance, minimizing energy losses during power transmission through wires. Its combination of hi...
Answer: C. Towards the train
Bernoulli principle states that fast moving fluids exhibit lower static pressure than slower surrounding air. A rapidly moving train drags adjacent air along with it, creating a high velocity air channel. Lower air press...
Answer: C. both interference and diffraction fringes
Light passing through slits produces interference fringes from multiple aperture interactions. Single slit diffraction effects occur simultaneously with multi slit interference patterns. Wave superposition creates combin...
Answer: C. 1/RC
Electrical circuits containing resistance and capacitance exhibit characteristic transient time constants. The product of resistance and capacitance determines the fundamental time scale of the circuit response. Frequenc...
Answer: D. Both B and C are correct
A valid unit vector must have a total calculated magnitude of exactly one. Squaring components of options B and C sums to one under square roots. Both mathematical representations satisfy the strict normalization conditi...
Answer: B. focus
The focal point is where parallel light rays converge or appear to diverge after refraction through a lens. Converging lenses bring incoming parallel rays together at a real principal focus point. Diverging lenses cause...
Answer: A. mean position
Simple harmonic motion achieves maximum velocity at the mean position. Restoring forces equal zero at the equilibrium center point. Potential energy converts entirely into kinetic energy at this mean position. Equilibriu...
Answer: C. 160 Hz
The first overtone of a stretched string corresponds specifically to its second harmonic frequency. Harmonic frequencies are integer multiples of the fundamental frequency for fixed string boundaries. Dividing the first...
Answer: C. conversion of water into ice in refrigerator
The conversion of water into ice inside a refrigerator involves heat rejection to the surroundings, which is not an adiabatic process. An adiabatic process is strictly defined as a thermodynamic change occurring without...
Answer: B. 5×106 Nm-2
Tensile stress is calculated by dividing the applied load by the cross-sectional area. Tensile strain is calculated by dividing the extension length by the original cord length. Young modulus equals tensile stress divide...
Answer: B. More than D.C. value
Half-wave rectifiers convert alternating current into unidirectional pulsating DC by blocking negative voltage halves. The resulting output waveform contains large gaps where current drops completely to zero during cycle...
Answer: D. Due to all reasons in A, B and C
Experimental errors in physical measurements can stem from multiple sources including operator inexperience, flawed techniques, and faulty equipment. No physical measurement can be performed with absolute perfection, mea...
Answer: C. force, acceleration
Newton second law of motion states that net force equals mass multiplied by acceleration vector. Because mass is a positive scalar quantity, multiplying acceleration by mass preserves its exact directional orientation. T...
Answer: A. Moving with speed of light
Photons always propagate at the speed of light through a vacuum without exception. Relativistic physics dictates that massless particles like photons cannot travel at any other speed. The constant speed of light in a vac...
Answer: A. Power of ten
Scientific notation formats numerical values as a coefficient multiplied by an integer power of ten. This mathematical formatting style simplifies the representation of extremely large or small numbers. Therefore, writin...
