Class 7 Science - Chapter Winds, Storms and Cyclones NCERT Solutions | Which of the statements given below is c

Explain why holes are made in hanging banners and hoardings.

Which one of the following place is unlikely to be affected by a cyclone.

(i) Chennai          (ii) Mangaluru (Mangalore)                                                                                                                                                                                              (iii) Amritsar        (iv) Puri

What planning is required in advance to deal with the situation created by a cyclone?

Suggest two methods to find out wind direction at a given place.

Fill the missing word in the blank spaces in the following statements:

(a) Wind is——————air.
(b) Winds are generated due to —————— heating on the earth.
(c) Near the earth’s surface __________air rises up whereas ___________ air comes down.
(d) Air moves from a region of ——— pressure to a region of ———.

How will you help your neighbours in case cyclone approaches your village/town?

State two experiences that made you think that air exerts pressure (other than those given in the text).

You want to buy a house. Would you like to buy a house having windows but no ventilators? Explain your answer.

State similarities and differences between the laboratory thermometer and the clinical thermometer.

State differences between acids and bases.

Classify the changes involved in the following processes as physical or chemical changes:
(a) Photosynthesis
(b) Dissolving sugar in water
(c) Burning of coal
(d) Melting of wax
(e) Beating aluminium to make aluminium foil
(f ) Digestion of food

Name the elements that determine the weather of a place.

In addition to the rock particles, the soil contains

(i) air and water
(ii) water and plants
(iii) minerals, organic matter, air and water
(iv) water, air and plants

Why does an athlete breathe faster and deeper than usual after finishing the race?

Match structures given in Column I with functions given in Column II.

Column I                           Column II
(i) Stomata                        (a) Absorption of water
(ii) Xylem                           (b) Transpiration
(iii) Root hairs                    (c) Transport of food
(iv) Phloem                        (d) Transport of water
                                          (e) Synthesis of carbohydrates

Fill in the blanks:

(a) Production of new individuals from the vegetative part of parent is called_____________.
(b) A flower may have either male or female reproductive parts. Such a flower is called_____________.
(c) The transfer of pollen grains from the anther to the stigma of the same or of another flower of the same kind is known as _____________.
(d) The fusion of male and female gametes is termed as _____________.
(e) Seed dispersal takes place by means of _____________, _____________ and _____________.

Classify the following as motion along a straight line, circular or oscillatory motion:

(i) Motion of your hands while running.
(ii) Motion of a horse pulling a cart on a straight road.
(iii) Motion of a child in a merry-go-round.
(iv) Motion of a child on a see-saw.
(v) Motion of the hammer of an electric bell.
(vi) Motion of a train on a straight bridge.

Why do organisms need to take food?

Explain how painting of an iron gate prevents it from rusting.

Describe how crystals of copper sulphate are prepared.

Draw the circuit diagram to represent the circuit shown in Fig.14.21.

Explain what you understand by sexual reproduction.

How would you test the presence of starch in leaves?

Suppose the two photographs, shown in Fig. 13.1 and Fig. 13.2, had been taken at an interval of 10 seconds. If a distance of 100 metres is shown by 1 cm in these photographs, calculate the speed of the blue car.

When the current is switched on through a wire, a compass needle kept nearby gets deflected from its north-south position. Explain.

The mountaineers carry oxygen with them because:

(a) At an altitude of more than 5 km there is no air.
(b) The amount of air available to a person is less than that available on the ground.
(c) The temperature of air is higher than that on the ground.
(d) The pressure of air is higher than that on the ground.

Sketch the cross section of soil and label the various layers.

Is the distilled water acidic/basic/neutral? How would you verify it?