Tag: light and shadow

Quizzes (9) Questions (122)

Questions Related to light and shadow

Multiple choice physics circular motion and gravitation elementary ideas of astronomy shadow formation and optical medium light and shadow

A satellite of mass $m$ is revolving around the earth at height $R$ (radius of the earth) from the earth's surface. Its potential energy will be :

  1. $mgR$
  2. $0.67 mgR$
  3. $-\dfrac{mgR}{2}$
  4. $0.33mgR$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The gravitational potential energy of a satellite of mass m at a distance r from the center of the earth is given by U = -G M m / r. Here, the height is R from the surface, so the distance from the center is r = R + R = 2R. Substituting M = g R^2 / G gives U = -mgR / 2.

Multiple choice physics light and shadow elementary ideas of astronomy shadow formation and optical medium the solar system nature and sources of light how light travels

Lunar eclipse occurs when earth comes in between sun and the moon. Solar eclipse occurs when moon comes in between sun and earth. This suggests that:

  1. Both eclipses occur on a new moon day

  2. Solar eclipse occurs on a new moon day

  3. Lunar eclipse occurs on a new moon day

  4. Both eclipses occur on a full moon day
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A solar eclipse occurs when the Moon passes between the Sun and

Earth, and the Moon fully or partially blocks the Sun. This

can happen only at new moon, when the Sun and the Moon are in

conjunction as seen from Earth in an alignment.
A lunar eclipse occurs when the Moon passes

directly behind the Earth into its shadow. This can occur only

when the Sun, Earth, and Moon are aligned exactly, or very

closely so, with the Earth in the middle. Hence, a lunar eclipse can only occur the night of a full moon.

Multiple choice physics light and shadow elementary ideas of astronomy shadow formation and optical medium the solar system nature and sources of light how light travels

Lunar eclipse occurs when the

  1. Sun comes between the Earth and the Moon.

  2. Moon comes between the Earth and the Sun.

  3. Earth comes between the Moon and the Sun.

  4. the Earth and Moon collide with each other.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The Moon moves around the Earth and the Earth moves around the Sun. During their revolutions, when the Moon, the Earth and the Sun come into a straight line keeping the Earth in between the Moon and the Sun, the lunar eclipse takes place.

Multiple choice physics light and shadow elementary ideas of astronomy shadow formation and optical medium the solar system nature and sources of light how light travels

The partial or complete hiding of one heavenly body by shadow of another is called

  1. Ellipse

  2. Eclipse

  3. Asteriod

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Eclipse is partial or complete hiding of one heavenly body by shadow of another.

Solar eclipse and lunar eclipse are two processes associated with earth, moon and sun.

Multiple choice physics light and shadow elementary ideas of astronomy shadow formation and optical medium the solar system nature and sources of light how light travels

When Earth comes in between Sun and Moon and casts its shadow on Moon. The ______ eclipse will occur.

  1. solar

  2. lunar

  3. either A or B

  4. none of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

During lunar eclipse, Earth comes between Sun and Moon in a straight line. The shadow of the Earth falls on the Moon and the Moon gets eclipsed.

Multiple choice physics light and shadow elementary ideas of astronomy shadow formation and optical medium the solar system nature and sources of light how light travels

Eclipse occurs when the Earth, Sun and Moon form:

  1. an isosceles triangle

  2. a straight line

  3. any random position

  4. a right angled triangle
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Eclipse occurs when Sun, Earth and Moon come in a straight line. The Earth or Moon that comes in between casts a shadow on Moon or Earth and form lunar or solar eclipse respectively.

Multiple choice physics light and shadow elementary ideas of astronomy shadow formation and optical medium the solar system nature and sources of light how light travels

When the Moon comes in between the Sun and Earth in a straight line, then ________ eclipse will occur.

  1. solar

  2. lunar

  3. either A or B

  4. none of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

During solar eclipse, Moon comes between Sun and the Earth. The Sun is eclipsed where the shadow of the Moon falls on the Earth.