• Skip to main content
  • Skip to primary sidebar
  • Skip to footer
  • NCERT Solutions
    • NCERT Books Free Download
  • TS Grewal
    • TS Grewal Class 12 Accountancy Solutions
    • TS Grewal Class 11 Accountancy Solutions
  • CBSE Sample Papers
  • NCERT Exemplar Problems
  • English Grammar
  • MCQ Questions

CBSE Tuts

CBSE Maths notes, CBSE physics notes, CBSE chemistry notes

Propagation of Light – Maharashtra Board Class 7 Solutions for General Science

Propagation of Light – Maharashtra Board Class 7 Solutions for General Science (English Medium)

MathematicsGeneral ScienceMaharashtra Board Solutions

Solution 1.a:

An object casts a shadow on a screen when an opaque object is placed between the object and a source of light. The opaque object does not allow the light to reach the screen, and hence, a shadow is formed.

Solution 1.b:

Light travels in a straight line and is called linear propagation of light. If any object is placed between the path of light, it casts a shadow. Thus, the formation of shadows takes place because of the linear propagation of light.

Solution 1.c:

The umbra and penumbra are formed with an extended source of light. The darker shadow is called umbra, and the fainter shadow is called penumbra.
Propagation of Light - Maharashtra Board Class 7 Solutions for General Science-- 1.c
Suppose MN (a torch of light) is an extended source of light and PQ is a ball (an opaque object) placed in front of it which blocks the light rays falling on the screen. Two types of shadows are formed on the screen – AD and BC. AD is a dark circular shadow surrounded by a fainter and a bigger region, BC. Hence, AD is the umbra and BC is the penumbra.

Solution 1.d:

A solar eclipse takes place when the Moon comes between the Sun and the Earth, and all three are in a straight line. This makes the shadow of the Moon fall on the Earth. A solar eclipse occurs on a New Moon day.

Solution 2.a:

The Sun, the Earth and the Moon must be in a straight line during their revolutions for an eclipse to occur because of the property of light called linear propagation.

Solution 2.b:

Two types of shadows are formed with an extended source of light, umbra and penumbra. The penumbra is faint because this region gets some light from some parts of the extended source of light.

Solution 2.c:

The Sun is an extended source of light and the Earth acts as a screen on which a shadow is formed. As the distance between the Earth and fast-moving objects like an aeroplane and a bird increases, the umbra becomes smaller and smaller till it completely disappears. Thus, an aeroplane or a bird does not cast a shadow when they are very high above the Earth.

Solution 2.d:

In the pinhole camera, the light enters through a very fine hole and is propagated in a straight line. An inverted image is formed in a pinhole camera because the light rays coming from the top and bottom of the object intersect at the pinhole. Thus, we get an upside down image in a pinhole camera because of the linear propagation of light through the hole of the pinhole camera.

Solution 3:

Group ‘A’ Group ‘B’
(a) Lunar eclipse Full Moon day
(b) White Prism
(c) Umbra Deep
(d) Penumbra Faint

Solution 4:

  1. As sunlight passes through a prism, it gets divided into seven colours of which the red colour is at the top.
  2. Sunlight is necessary for the growth of plants.
  3. The path of light is linear.
  4. A rainbow appears on the opposite of the Sun.

Primary Sidebar

NCERT Exemplar problems With Solutions CBSE Previous Year Questions with Solutoins CBSE Sample Papers

Recent Posts

  • MCQ Questions with Answers for Class 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, and 1 all Subjects
  • Angle, Types of Angles
  • AND gate is formed by using two? 1)OR 2)NAND 3)NOT 4)NOR
  • And expression for one minus the quotient of one and a number X?
  • What is average human body temperature in Kelvins?
  • How many moles of caffeine are in a cup, and how many molecules of caffeine?
  • How far will the car have traveled in that time?
  • What is its atomic number?
  • How many neutrons does it have?
  • An atom loses electrons to form what?
  • What is the atomic number of this atom?
  • Which one of these is the answer?
  • What is its concentration?
  • Can an equilateral triangle also be isosceles?
  • What is the charge of an alpha particle?

Footer

Maths NCERT Solutions

NCERT Solutions for Class 12 Maths
NCERT Solutions for Class 11 Maths
NCERT Solutions for Class 10 Maths
NCERT Solutions for Class 9 Maths
NCERT Solutions for Class 8 Maths
NCERT Solutions for Class 7 Maths
NCERT Solutions for Class 6 Maths

SCIENCE NCERT SOLUTIONS

NCERT Solutions for Class 12 Physics
NCERT Solutions for Class 12 Chemistry
NCERT Solutions for Class 11 Physics
NCERT Solutions for Class 11 Chemistry
NCERT Solutions for Class 10 Science
NCERT Solutions for Class 9 Science
NCERT Solutions for Class 7 Science
MCQ Questions NCERT Solutions
CBSE Sample Papers
cbse ncert
NCERT Exemplar Solutions LCM and GCF Calculator
TS Grewal Accountancy Class 12 Solutions
TS Grewal Accountancy Class 11 Solutions