How many internal reflections of ligh take place in the formation of primary rainbow?

How many internal reflections of ligh take place in the formation of primary rainbow?

The best evidence for the existence and movement of particles in liquids was given by___?

 Which of the following statements is/are correct?
I. The force between two bodies is directly proportional to the product of their masses.
II. The force between two bodies is inversely proportional to the square of the distance between them.
III. The force between two bodies is the ratio of their masses.

Aluminium is manufactured from ___?

The early attempt to classify elements as metals and non-metals was made by ___?

Which is the device used to detect and measure small electric current in a circuit?

The lowest temperature at which an oil gives sufficient vapours to form an explosive mixture with air is known as :-

The value of G in the formula for gravitational force depends on -

When a hanging carpet is beaten with a stick, the dust particles in it start coming out of it. This phenomenon can be explained by making use of -