Match the items given in Column I with one or more items of Column II.
Column I Column II
(a) A plane mirror (i) Used as a magnifying glass.
(b) A convex mirror (ii) Can form image of objects spread over a large area.
(c) A convex lens (iii) Used by dentists to see enlarged image of teeth.
(d) A concave mirror (iv) The image is always inverted and magnified. (e) A concave lens (v) The image is erect and of the same size as the object.
(vi) The image is erect and smaller in size than the object.
Column I Column II
(a) A plane mirror (v) The image is erect and of the same size as the object.
(b) A convex mirror (ii) Can form image of objects spreads over a large area.
(c) A convex lens (i) Used as a magnifying glass.
(d) A concave mirror (iii) Used by dentists to see enlarged image of teeth.
(e) A concave lens (vi) The image is erect and smaller in size than the object.
1. A plane mirror: A plane mirror have a flat reflective surface. The angle of reflection is always equals to the angle of incidence for the light rays which strikes the plane mirror. The angle formed by the incident ray and surface of normal is called the angle of incidence.
2. A convex mirror: A convex mirror is a diverging mirror in which the reflective surface bulges towards the light Source. The image formed by convex mirrors are smaller than the object but gets larger as they approach.
3. Concave mirror: A concave mirror has a reflective surface that is curved inwards and away from the light source. Concave mirrors are widely used in headlights of auto mobiles motor vehicles, torch lights etc.
4. Convex lens: The convex lens is a lens that converges rays of light that convey parallel to its principal axis which is relatively thick cross the middle and thin at the lower and upper edges. A convex lense in thinner in the middle and thicker towards the edges.
5. Concave lens: A concave lens is a lens that possesses at least one surface that curves inwards. It is a diverging lens, meaning that it spreads out light rays that have been refracted through it. A concave lens is thinner at its edges, and is used to correct short sightedness.
Popular Questions of Class 7 Science
- Q:-
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 - Q:-
Given below is a crossword puzzle based on this lesson. Use hints to fill in the blank spaces with letters that complete the words.
Down Across
(D) 1 : Thorough washing (A) 1 : Keeps warm
2 : Animal fibre 2 : Its leaves are eaten by silkworms
3 : Long thread like structure 3 : Hatches from egg of moth
- Q:-
Sketch the cross section of soil and label the various layers.
- Q:-
Take three test-tubes. Fill æth of each with water. Label them A, B and C. Keep a snail in test-tube A, a water plant in test-tube B and in C, keep snail and plant both. Which test-tube would have the highest concentration of CO2?
- Q:-
When baking soda is mixed with lemon juice, bubbles are formed with the evolution of a gas. What type of change is it? Explain.
- Q:-
Here is a crossword puzzle: Good luck!
Across
3. Liquid waste products
4. Solid waste extracted in sewage treatment
6. A word related to hygiene
8. Waste matter discharged from human bodyDown
1. Used water
2. A pipe carrying sewage
5. Micro-organisms which causes cholera
7. A chemical to disinfect water - Q:-
Match the items in Column I with those in Column II:
Column I Column II
(i) A home for living organisms (a) Large particles
(ii) Upper layer of the soil (b) All kinds of soil
(iii) Sandy soil (c) Dark in colour
(iv) Middle layer of the soil (d) Small particles and packed tight (v) Clayey soil (e) Lesser amount of humus - Q:-
Write one similarity and one difference between the nutrition in amoeba and human beings.
- Q:-
An iron ball at 40°C is dropped in a mug containing water at 40°C. The heat will
(a) flow from iron ball to water.
(b) not flow from iron ball to water or from water to iron ball.
(c) flow from water to iron ball.
(d) increase the temperature of both. - Q:-
Why does an athlete breathe faster and deeper than usual after finishing the race?
Recently Viewed Questions of Class 7 Science
- Q:-
How do elephant living in the tropical rainforest adapt itself?
- Q:-
Describe how crystals of copper sulphate are prepared.
- Q:-
Choose the correct option from the following:
Which part of the plant takes in carbon dioxide from the air for photosynthesis?
(i) Root hair (ii) Stomata (iii) Leaf veins (iv) Sepals - Q:-
Explain how painting of an iron gate prevents it from rusting.
- Q:-
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. - Q:-
Name the elements that determine the weather of a place.
- Q:-
Will the compass needle show deflection when the switch in the circuit shown by Fig.14.24 is closed?
- Q:-
Make sketches of the two stages in the life history of the silk moth which are directly related to the production of silk.
- Q:-
The rear view mirror of a car is a plane mirror. A driver is reversing his car at a speed of 2 m/s. The driver sees in his rear view mirror the
image of a truck parked behind his car. The speed at which the image of the truck appears to approach the driver will be(i) 1 m/s (ii) 2 m/s
(iii) 4 m/s (iv) 8 m/s - Q:-
Name any two effects of electric current.
- NCERT Chapter