Improvement In Food Resources — Science STD 9 — Question

A person moves a distance of 3km towards east, then 2km towards north and 3.5km towards east. Find:

1. Distance covered by the person.
2. Displacement.

Give an example each for the mixture having the following characteristics. Suggest a suitable method to separate the components of these mixtures: Two volatile components with appreciable difference in boiling points.

What is an epidemic disease?

List any three human activities which would lead to an increase in the carbon dioxide content of air.

An object is moving along a straight line with uniform acceleration. The following table gives the velocity of the object at various instants of time:

Time (in sec.):	0	1	2	3	4	5	6
Velocity (in m/s):	2	4	6	8	10	12	14

Plot the graph. From the graph,

1. Find the velocity of the object at the end of 2.5 seconds.
2. Calculate the acceleration.
3. Calculate the distance covered in the last 4 seconds.

Where do bone and cartilage cells reside?

Given examples of different rabi and kharif crops.

What is reverberation? How can it be reduced?

What does the term plasmolysed mean when used to describe a cell?