Chhattisgarh State Class 7 Science Chapter 15 Solution

Chhattisgarh State Board Class 7 Science Chapter 15 Static Electricity Exercise Multiple Choice, Questions and Answers here.

Answer these

(1) How can we check whether an object is charged?

Answer:- (1) We can check whether an object is charged on the basis of whether they attract or repeal.

(2) Like charges repeal each other and unlike charge attract each other.

(3) “Repulsion between two objects can prove that both objects are charged”

(2) How many type of charges are there? Write their names.

Answer:- (1) There are two types of charges

(2) Positive charges (+) and Negative charges (-)

(3) How many way can be used to charged an object?

Answer:- (1) These different method can be used to charge an object.

(2) And they are:-

(i) Charging by friction

(ii) Charging by contact

(iii) Charging by induction

Answer these

(1) What is a lightening conductor?

Answer:- Lightening conductor is a conductor use to prevent tall building from getting struck by lightning.

(2) On what principle does the electroscope work?

Answer:- The electroscope work on principle like charges repeal each other while unlike charges attracts each other.

Question for practice

(1) Choose the correct answer:-

On rubbing two objects (a) and (b) if (a) attain negative (-) charge then (b) will have –

(a) Negative charge

(b) Negative and positive charge both

(c) Positive charge

(d) None of these

Answer:- (c) Positive charge.

(2) Out of the following, which one can not be easily charge by friction?

(a) Glass rod

(b) Ball of wool

(c) Copper rod

(d) Balloon filled with air

Answer:- (c) Copper rod.

(3) Human body for electric current is –

(a) An insulator

(b) Sometime a conductor/sometime an insulator

(c) A conductor

(d) None of these

Answer:- (c) A conductor.

(4) When two objects are rubbed together, then they develop –

(a) Opposite charge

(b) Same charge

(c) No charge

(d) Sometime opposite sometime same charge

Answer:- (a) Opposite charge.

(5) Lightening conductor are made of –

(a) Of metal

(b) Of non-metal

(c) By painting the wall

(d) Of wood.

Answer:- (a) Of metal.

(2) Fill in the blank –

(a) The materials that allow electric current to pass through them are called ——.

Answer:- Conductors.

(b) Like charge —– each other, while unlike charges —- each other.

Answer:- Repeal, Attract.

(c) The mechanism used to protect the buildings from lighting is called ——- ——-

Answer:- Lightning, conductor.

(d) When two objects are rubbed with each the nature of the charges produced on them is opposite.

(3) Write the name of two conductors and two insulator for electricity

Answer:- (i) Conductors for electricity:-

(1) Copper            (2) Silver

(ii) Insulator for electricity:-

(1) Rubber       (3) Glass

(4) Why does the charge on an object vanish when the object come in correct with our body?

Answer:- The charge on an object vanish when the object come in contact with our body, the charge flow through the body in the earth. Therefore charge is vanish.

(5) What precautions should we take to protect ourselves for lighting?

Answer:- Precaution should we take to protect ourselves for lightning are –

(i) Avoid the mobile during lighting

(ii) We should avoid to go outside during thunderstorm.

(6) Give reasons –

(a) It is unsafe to stand under tree while it is raining and lightning.

Answer:- It is unsafe to stand under tree while it is raining and lighting because sometime at the time of lighting, the discharge flows to the ground through trees.

(b) The feather of a peacock stretches on being rubbed between two paper.

Answer:- The feather of a peacock stretches or being rubbed between two paper because if an object is charged by contact then it develops a charge of the same kind as it possessed by the object with which it is touched.

Updated: February 7, 2021 — 1:23 am

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