Audio cassettes are coated with which oxide?
Answer : D. iron
Transfer of heat by molecular collision is
Answer : B. conduction
Colour formation in the films is due to
Answer : C. Interference
The one used in the preparation of lenses and prisms
Answer : B. Flint glass
Name the organism which flies with the help of ultrasonics?
Answer : B. bat
Which of the following regulates and controls the entry of light into human eye?
Answer : B. iris