Introduction to Biotechnology — Science STD 9 — Question

How can one produce sound?

Nowadays, an electronic device – the cell phone – is very popular. From a mobile shop near your house, find out how they dispose off old and broken down cell phones.

Velocity of sound In air at 0°C is 332m/s It increases by 0.6mIs for each degree Celsius rise In temperature. What will be the velocity of sound at 60°C?

An object is placed at a distance of 36 cm from a concave mirror of focal length 12 cm. Find the image distance.

A rocket of mass 100 tonnes is propelled with a vertical velocity 1 km/s. Calculate kinetic energy.

Bivalent acidic radicals

Hydrogen gas is filled in two identical bottles, A and B, at the same temperature. The mass of hydrogen in the two bottles is 12 gm and 48 gm respectively. In which bottle will sound travel faster? How may times as fast as the other?

If 0.2 mol of the following substances are required how many grams of those substances should be taken? Sodium chloride, magnesium oxide, calcium carbonate

The principal axis of a mirror

Define : Heredity