Units and Measurements — Physics STD 11 Science — Question

A substance absorbs heat Q₁ in going from one state to another and releases Q₂ in coming from the second state to the first state. How much work is done by the substance and what is the change in the internal energy of the substance?

Apply first law of thermodynamics for isothermal expansion of an ideal gas.

In a real gas the internal energy depends on temperature and also on volume. The energy increases when the gas expands isothermally. Looking into the derivation of C_P - C_v = R, find whether C_P - C_v will be more than R, less than R or equal to R for a real gas.

What is the difference between a tone and a note?

What is the total energy of a simple harmonic oscillator?

In a progressive wave, what is the path difference between a node and the antinode immediately following it. And phase difference?

If a drop of water falls on a hot plate, it takes long time to evaporate. Why?

A man is standing on top of a building 100m high. He throws two balls vertically, one at t = 0 and other after a time interval (less than 2 seconds). The later ball is thrown at a velocity of half the first. The vertical gap between first and second ball is +15m at t = 2s. The gap is found to remain constant. Calculate the velocity with which the balls were thrown and the exact time interval between their throw.

What happens to surface tension, when impurity is mixed in liquid?

In an experiment on photoelectric effect, a photon is incident on an electron from one direction and the photoelectron is emitted almost in the opposite direction. Does this violate conservation of momentu?