Structure of the Atom — Science STD 9 — Question

The method maximum used in cattle breeding is:

1. Random mating.
2. Artificial insemination.
3. Controlled breeding.
4. Superovulation and embryo transfer.

The ratio of moles of atoms in 12g of magnesium and 16g of sulphur will be:

1. 3 : 4
2. 4 : 3
3. 1 : 1
4. 1 : 2

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

1. Newton's third law of motion.
2. Newton's law of gravitation.
3. Newton's first law of motion.
4. Newton's second law of motion.

Why do clothes dry faster on a windy day:

P.E of a spring increases when it is in the state of:

A water tanker filled up to two-thirds of its tank with water is running with a uniform speed. When the brakes are suddenly applied, the water in its tank would:

1. Move backward.
2. Move forward.
3. Rise upwards.
4. Remain unaffected.

Which of the following is not an example of a motion with a constant speed but variable velocity:

Cardiac muscle fibres are:

What will be the mass of 5 mole of SO₂?