PART - 1 CH - 2 Motion in a Straight Line — Physics STD 11 Science — Question

Explain this statement clearly: “To call a dimensional quantity ‘large’ or ‘small’ is meaningless without specifying a standard for comparison”. In view of this, reframe the following statements wherever necessary:

1. Atoms are very small objects
2. A jet plane moves with great speed
3. The mass of Jupiter is very large
4. The air inside this room contains a large number of molecules
5. A proton is much more massive than an electron
6. The speed of sound is much smaller than the speed of light.

Name the waves which do not require any material medium for their propagation.

A ladder is learning against a wall. If it slips, where will its instantaneous center of rotation be?

What is called the dimension of physical quantity?

Why can water in a metallic pot be boiled quickly if the bottom of the pot is made black and rough than highly polished?

Why does the time period of a swing not change when two persons sit on it instead of one?

A thief jumps from the roof of a house with a box of weight on his head. What will be the weight of the box as experienced by the thief during jump?

A body of mass 2kg initially at rest moves under the action of an applied horizontal force of 7N on a table with coefficient of kinetic friction = 0.1. Compute the: Work done by the net force on the body in 10s.

Give any one example in one demensional motion.