A brass ball is hanging from a stiff cotton thread. Draw a neat labelled diagram showing the forces acting on the brass ball and cotton thread.
The distance between two bodies is doubled. How is the magnitude of the gravitational force between them affected?
A solid of mass 50 g at 150°C is placed in 100 g of water at 11°C, when the final temperature recorded is 20°C. Find the specific heat capacity of the solid. (specific heat capacity of water = 4.2 J/g°C)
How is the refractive index of a material related to:
(i) real and apparent depth?
(ii) velocity of light in vacuum or air and the velocity of light in a given medium?
(i) When an object is placed under water (any other medium) than observing it from
outside the water (or medium) it appears to be raised above.
The ratio of real depth and apparent depth is equal to the refractive index of the
medium.
Refractive index, µ =
(ii) The relation between Refractive Index and Velocity of Light.
The refractive index of the medium is the ratio of the velocity of light in vacuum (or air) to the velocity of light in that medium.