Mechanical Waves | Old is Gold | Class XII
Mechanical Waves
Short
1. Why sound made/produced at a distance can be heard distinctly at night
Quantity of Heat- Old is Gold
Why does food cook faster in a pressure cooker than in an open pot?
How can water be boiled in
Refraction at plane surfaces- Old is Gold
Why do in summer, roads often appear to be covered with water when seen from a distance? Explain.
Why
Alternating Currents | Old is Gold | XII
Short Questions
1. Why do we prefer a choke coil to rheostat in an a.c. current?
2. What is meant buy independence of an a.c. current?
3.
First law of thermodynamics- Old is Gold
Air escaping from an air-hose at a gas station always feels cold. Why?
Differentiate between isothermal and adiabatic change.