The most familiar form of radiant energy in sunlight that cause tanning and has the potential for causing melanoma in humans is called
Answer : A. ultra-violet radiation
Ball bearings are used in bicycles, cars, etc., because?
Answer : A. The effective area of contact between the wheel and axle is reduced
Which one among the following satellites is used to reflect the radio-signals back to the Earth?
Answer : C. Passive satellite
A cold soft drink is kept on balance. When the cap is opened, then the weight
Answer : D. first increase then decrease
When a red glass is heated in dark room it will seem
Answer : B. green
How is the pressure cooker work?
Answer : C. High pressure inside the cooker rises the boiling point of water