Physics Fundamentals | MCQs

Explanation

Instantaneous velocity at any point on a curved path is directed tangentially to the curve.

It indicating the direction of motion at that moment.

Explanation

Coulomb's Law states that the magnitude of the electrostatic force (F) between two point charges (q1 and q2) is directly proportional to the product of the charges and inversely proportional to the square of the distance (r) between them.

Mathematically, this is expressed as: F ∝ (q1 × q2) / r².

This law describes the relationship between electric charges and the force they exert on each other.

Explanation

The distance between two successive particles that are in the same state of vibration is called Wavelength.

It is measured as the distance between two consecutive crests or troughs in a wave.

Explanation

In transverse waves, the portion above the mean level is called wave crest.

The crest represents the highest point of the wave, while the trough is the lowest point below the mean level.

Explanation

The unit of the decay constant is s⁻¹.

It represents the probability per second that a nucleus will decay.

It indicating how quickly a radioactive substance undergoes decay.

Explanation

The potential through which an electron should be accelerated to lift an atom's electron from the ground state to a higher state is known as excitation potential.

This energy excites the electron without completely removing it from the atom.

Explanation

Photoelectric effect does not demonstrate the wave nature of light; it shows light behaving as particles (photons).

The phenomena of diffraction, polarization, and interference are clear evidence of light's wave nature.

Explanation

The value of Planck's constant is 6.63 × 10⁻³⁴ Js.

This constant is fundamental in quantum mechanics.

It relating the energy of a photon to its frequency.

Explanation

Full wave rectification is given by four diodes connected in bridge type arrangement.

This configuration allows both halves of the A.C. waveform to be used, producing a smoother and more efficient output compared to half-wave rectification.

Explanation

In an ideal transformer, power input is equal to power output.

This is based on the principle of conservation of energy.

It means that the transformer is assumed to have no losses; therefore, the input power (from the primary coil) equals the output power (to the secondary coil).