Question

Hi guys I am here with one more 100 points question please answer fast as this is my all points.
Chapter 15 – Light
Worksheet-Grade VII
Choose the correct answer:
1. Concave lens always forms
a. Real image
b. Virtual image
c. Inverted image
d. Magnified image
2. Mirror used a shaving mirror is
a. Convex mirror
b. Bifocal mirror
c. Concave mirror
d. Plane mirror
3. Which colour of light scattered least
a. Red
b. Blue
c. Green
d. Orange
4. White light consist of
a. 3 colours
b. 5 colours
c. 7 colours
d. 9 colours
5. Match the following
Column A Column B
a. Moon i. Natural biological luminous
b. Sun ii. Non-luminous
c. Brick iii. Reflector
d. Mirror iv. Opaque
e. Glow-worm v. Luminous
6. Write T for true and F for false statements. a. Light is a form of energy which can not be seen.
b. Light travels slower than sound.
c. Plane mirror is used in periscope.
d. Bending of rays of light due to change in medium is called refraction.
e. Plane mirror has fixed focal length.
7. What is focal length of a mirror? How it varies with curvature?
8. Why a paper held in sunshine at focus of a convex lens burns?
9. Write difference between concave and convex mirror?
10. Give one word that means
a. Bouncing back of rays of light.
b. Band of seven colours obtained on dispersion of white light.
c. Mirror used as rear view mirror in automobiles.
d. Image formed by plane mirror.
e. Sequence of colours of spectrum.

Answer 1

Answer:

1 ) answers

b) virtual images

2 ) answers

a ) convex mirror

3 ) answers

a ) red

your answer........friend

Answer 2

Answer:

1. virtual image
2. c
3. a
4. the answer is 7
5. sorry its too long
6. a F B. F C. t F
7. The focal length ( f ) is the distance from a lens or mirror to the focal point ( F ). This is the distance from a lens or mirror at which parallel light rays will meet. ... Light rays that are parallel to each other, but not to the optical axis, will meet on the focal plane.
8. Convex Lens Concentrates The Light Energy To One Spot On The Paper So That The Heat Energy Accumulates On That One Small Spot Of Paper. As The Heat Increases, Combustion Will Occur When The Spot Becomes Too Hot & The Paper Burns
9. If the inner side of the spherical mirror is reflecting, it is called a concave mirror. If the outer side of the spherical mirror is reflecting, it is called a convex mirror. Concave mirrors can form inverted and real images and also virtual and erect images.
10. 1. reflective ray 2. vibgyor 3.