‘Vishu’ is which state’s New Year

Which of the following statements is true about sound?  

When a passenger in a moving bus is suddenly thrown forward when the bus stops, this is explained by:

What was invented by 'Zacharias Janssen'?

If the temperature of a place increases suddenly, the relative humidity –

Global warming is expected to result in

An electron in a hydrogen atom de-excites from the 4th to the 2nd level. The wavelength of emitted photon falls in which series?

Two charges, +3 µC and –3 µC, are placed 1 m apart in vacuum. What is the electrostatic potential energy of the system?

A body is thrown vertically upward. The work done by gravity is: 

A uranium nucleus undergoes fission and releases 200 MeV per event. If 1 gram undergoes complete fission, the energy released in kWh is: