Science

Which is the metal through which X-ray does not pass?
Lead

Which is the vtamin produced in our body by ultra violet rays in the sun?
VitaminD

Which is the unit for measuring the intensity of sound wave?
Decibel

Which scientific principle has been used in the brakes of vehicles?
Friction

What is the basic principle behind submarines?
Principles of buoyancy of Archimedes

Which device is used in atomic reactors to increase the velocity of ions?
Cyclotron

Who invented Cyclotron?
E.O.Lawrence

Sound is not heard in the moon. Why?
There is no atmosphere in the moon

In the German Silver (an alloy) how much silver is present?
Zero percentage

9What is the use “anemometer”?
It is used for measuring the speed of airflow


Why is there a loud explosion when electric bulb bursts?
Because air rushes suddenly into the vacuum space of the bulb