Duduli

Entropy(S) is a thermodynamic state function that measures the degree of energy dispersal or randomness/disorder of a system. Unit:- J K-¹ For Specific entropy  Unit :- J Kg K-¹   ●                         dS=dQ/T For reversible process ds=0 For irreversible process ds>0 Examples :- ●Ice melting → entropy increases. ●Water evaporating → entropy increases. ●Gas expanding freely → entropy increases. ●Heat naturally flowing from hot to cold → total entropy increases.

Electromagnetic induction is the phenomenon of production of an induced emf (electromotive force) in a closed circuit whenever the magnetic flux linked with the circuit changes. The induced emf is given by e=-dΦ/dt For a coil of N-turns e=-NdΦ/dt where magnetic flux is Φ=BAcosθ Lenz's law:- The induced current always flows in such a direction that it opposes the change in magnetic flux that produces it.

Resonance is the phenomenon in which a system oscillates with maximum amplitude when the frequency of the external periodic force equals its natural frequency.

A wave function (ψ) is a mathematical function that describes the quantum state of a particle. Its squared magnitude gives the probability density of finding the particle at a particular position. |ψ|² = Probability density In short : The wave function tells us what we can know about a quantum particle and where it is likely to be found.

Quantum tunneling is a phenomenon where a quantum particle can pass through a potential barrier even when its energy is less than the barrier height. In classical physics: ❌ Impossible In quantum physics: ✅ Possible Example : It is responsible for α-decay and is used in scanning tunneling microscopes (STM).

The Doppler effect is the apparent change in frequency of a wave when there is relative motion between the source and the observer. ●Source approaching → frequency increases → higher pitch ●Source moving away → frequency decreases → lower pitch Example :-The pitch of an ambulance siren sounds higher as it approaches you and lower as it moves away.