English Medium कक्षा ९ - CBSE Question Bank Solutions for Science

Give one example of a motion where an object does not change its speed but its direction of motion changes continuously.

Write the formula to calculate the speed of a body moving along a circular path. Give the meaning of each symbol which occurs in it.

A train starting from rest moves with a uniform acceleration of 0.2 m/s² for 5 minutes. Calculate the speed acquired and the distance travelled in this time.

The tip of seconds’ hand of a dock takes 60 seconds to move once on the circular dial of the clock. If the radius of the dial of the clock be 10.5 cm, calculate the speed of the tip of the seconds’ hand of the clock. `("Given"  π= 22/7)`.

A car is moving on a straight road with uniform acceleration. The speed of the car varies with time as follows :
Time (s)              :     0          2         4          6       8         10
Speed (m/s)       :     4          8       12        16     20         24
Draw the speed-time graph by choosing a convenient scale. From this graph :

(1) Calculate the acceleration of the car.
(2) Calculate the distance travelled by the car in 10 seconds.

The graph given alongside shows how the speed of a car changes with time:

(i) What is the initial speed of the car ?
(ii) What is the maximum speed attained by the car ?
(iii) Which part of the graph shows zero acceleration ?
(iv) Which part of the graph shows varying retardation ?
(v) Find the distance travelled in first 8 hours.

A body is thrown vertically upwards. Its velocity keeps on decreasing. What happens to its kinetic energy as its velocity becomes zero?

Explain the following giving an example.

Saturated solution

Explain the following giving an example.

Suspension

Name the physical state of matter which can be easily compressed.

Name two gases which are supplied in compressed form in homes and hospitals.

Write the full forms of the following

1. LPG
2. CNG

Which of the two diffuses faster : a liquid or a gas?

State whether the following statement is true or false :

Red-brown bromine vapour diffuse into air in a gas jar but the colourless air molecules do not diffuse into bromine vapour.

A bottle of perfume was opened in a room. The smell of its vapours spread in the entire room. Name the property of gases which is responsible for this behaviour of perfume vapours.

If the fish is being fried in a neighbouring home, we can smell it sitting in our own home. Name the process which brings this smell to us.

Fill in the following blank with suitable words :

Solid, liquid and gas are the three ........................ of matter.

Fill in the following blank with suitable words :

At room temperature, the forces of attraction between the particles of solid substances are ....................... then those which exist in the gaseous state.

Explain the various factors which are responsible for the loss of stored food grains.

Explain the various preventive measures which are taken before storing the food grains.