Structure of the Atom — Science STD 9 — Question

The law of gravitation gives the gravitational force between:

1. The earth and a point mass only.
2. The earth and the sun only.
3. Any two bodies having some mass.
4. Any two charged bodies only.

Trabeculae is the transformation of:

The sound propagates in a gaseous medium by:

Which of the following is the seperation technique to seperate mercury and water:

All atoms contain neutrons in their nuclei except:

A car A is travelling on a straight level road with a uniform speed of 60km/h. It is followed by another car B. Which is moving with a speed of 70km/h. When the distance between them is 2.5km, the car B is given a deceleration of 20km/h2. After how much time will B catch up with A?

Trapped dust particles are pushed out of respiratory tract by:

Smooth muscle fibres are:

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

Which of the following are compounds?

1. CO
2. No
3. NO
4. Co

1. (i) and (ii)
2. (ii) and (iii)
3. (i) and (iii)
4. (ii) and (iv)