Q.7 Short answer type questions. (Any 5)
(1) State at least two ways of conservation of water.
(2) What are the uses of artificial satellite.
(3) What are the causes of blindness?
(4) What are the causes of earth quake?
(5) What are the components necessary for the flow of electric current ?
(6) Differentiate between the noise and musical sound.
(7) Differentiate between contact and non contact forces. Give examples.
Answers
Answer:
Que.1 State at least two ways of conservation of water.
Ans. 1. Prefer to use the shower, not always a bath.
2.When brushing your teeth, close the tap!
Que.2 What are the uses of artificial satellite.
Ans. They are used in communication. They are used in weather forecasting system. They are used in GPS (Global Positioning System)
Que.3 What are the causes of blindness?
Ans. 1.Cataract. The world's most common cause of blindness, cataract affects 65 million people. ...
2.Glaucoma. The third leading cause of blindness, glaucoma can be treated with medication. ...
3.River blindness. ...
4.Trachoma. ...
5.Uncorrected refractive error (URE)
Que.4 What are the causes of earth quake?
Ans.4 Earthquake is caused by accidentally slipping. ... When the stress on the shore is greater than friction, an earthquake occurs that releases energy into waves that travel through the earth's crust and cause tremors that we feel. California has two plates - the Pacific Plate and the North American Plate.
Que.5 What are the components necessary for the flow of electric current ?
Ans. To produce an electric current, three things are needed: a supply of electric charges (electrons) which are free to flow, some form of push to move the charges through the circuit and a pathway to carry the charges. The pathway to carry the charges is usually a copper wire.
Que.6 Differentiate between the noise and musical sound.
Ans. Music is a sound that produces a pleasing sensation. It is produced by nature, musical instruments, human voice, etc. Noise is an unwanted and unpleasant sound produced by horns of vehicles, by machines, etc. If a musical sound is made too loud, it becomes a noise.
Que.7 Differentiate between contact and non contact forces. Give examples.
Ans. A non-contact force is a force which acts on an object without coming physically in contact with it. The most familiar non-contact force is gravity, which confers weight. In contrast a contact force is a force applied to a body by another body that is in contact with it.