Improvement in Food Resources — Science STD 9 — Question

........ management is controlling the selection, timing and amount of nutrient supply to the crops:

Perforated card boards are used in halls, for:

The atomic number of calcium and argon are 20 and 18 respectively, but the mass number of both these elements is 40. What is the name given to such a pair of elements?

Which of the following effect cannot be produced by an unbalanced force acting on a body?

1. Change in speed of the body.
2. Change in shape of the body.
3. Change in direction of motion of the body.
4. Change in state of rest of the body.

Each of the following statement describes a force acting. Which force is causing work to be done?

1. The weight of a book at rest on a table.
2. The pull of a moving railway engine on its coaches.
3. The tension in an elastic band wrapped around a parcel.
4. The push of a person's feet when standing on the floor.

The dyes present in fountain pen ink can be separated by the technique of:

A group of related genera, with still less number of similarities as compared to the genus and species, constitutes.

1. Order.
2. Class.
3. Family.
4. Division.

Paddy and soya beans are:

In SONAR we use:

1. Ultrasonic waves.
2. Infrasonic waves.
3. Radio waves.
4. Audible sound waves.

You are given a mixture of iodine in alcohol called tincture iodine. Which method will you use to recover both, iodine as well as alcohol, from this mixture?