English Medium Class 9 - CBSE Question Bank Solutions

What happens when rain falls on soil without vegetational cover?

Find out the correct sentence about manure

1. Manure contains large quantities of organic matter and small quantities of nutrients.
2. It increases the water-holding capacity of sandy soil.
3. It helps in draining out an excess of water from clayey soil.
4. ts excessive use pollutes the environment because it is made of animal excretory waste.

Soil supply ______ nutrients to plants.

______ nutrients are required in large quantity and called as ______.

Differentiate between compost and vermicompost?

Differentiate between compost and vermicompost?

Arrange these statements in the correct sequence of preparation of green manure.

(a) Green plants are decomposed in soil.

(b) Green plants are cultivated for preparing manure or crop plant parts are used.

(c) Plants are ploughed and mixed into the soil.

(d) After decomposition it becomes green manure.

When will you say a body is at uniform acceleration?

Name the three sub-atomic particles of an atom.

Helium atom has an atomic mass of 4 u and two protons in its nucleus. How many neutrons does it have?

Compare the properties of electrons, protons and neutrons.

A neutron is formed by an electron and a proton combining together. Therefore, it is neutral.

The mass of an electron is about `1/2000` times that of proton.

A farmer moves along the boundary of a square field of side 10 m in 40 s. What will be the magnitude of displacement of the farmer at the end of 2 minutes 20 seconds?

Which of the following is true for displacement?

1. It cannot be zero.
2. Its magnitude is greater than the distance travelled by the object.

An athlete completes one round of a circular track of diameter 200 m in 40 s. What will be the distance covered and the displacement at the end of 2 minutes 20 s?

An object experiences a net zero external unbalanced force. Is it possible for the object to be travelling with a non-zero velocity? If yes, state the conditions that must be placed on the magnitude and direction of the velocity. If no, provide a reason.

Why is it difficult to hold a school bag having a strap made of a thin and strong string?

In which of the three media, air, water or iron, does sound travel the fastest at a particular temperature?

Flash and thunder are produced simultaneously. But thunder is heard a few seconds after the flash is seen, why?