Secondary School (English Medium) (5 to 8) इयत्ता ८ - CBSE Question Bank Solutions for Science

Name the first Reserve Forest of India.

Mention the aim of Forest (Conservation) Act.

In the circuit shown in the following figure, when the circuit is completed, the hammer strikes the gong. Which of the following force is responsible for the movement of hammer?

If we apply oil on door hinges, the friction will

You might have noticed that when used for a long time, slippers with rubber soles become slippery. Explain the reason.

We have a stringed musical instrument. The string is plucked in the middle first with a force of greater magnitude and then with a force of smaller magnitude. In which case would the instrument produce a louder sound?

Which of the following solutions will not make the bulb in figure?

We can see a non-luminous object when the light

Light is falling on surfaces S₁  S₂ and S₃ as shown in the following figure.

Surfaces on which the angle of incidence is equal to the angle of reflection is/are

A small hole P is made in a piece of cardboard. The hole is illuminated by a torch as shown in the following figure. The pencil of light coming out of the hole falls on a mirror.

At which point should the eye be placed, so that the hole can be seen?

Two mirrors A and B are placed at right angles to each other as shown in the following figure.

A ray of light incident on mirror A at an angle of 25° falls on mirror B after reflection. The angle of reflection for the ray reflected from mirror B would be

How many times is a ray of light reflected by two plane mirrors placed parallel and facing each other?

The angle between incident ray and reflected ray is 60°. What is the value of angle of incidence?

The distance between the object and its image formed by a plane mirror appears to be 24 cm. What is the distance between the mirror and the object?

Draw figure showing the position of the plane mirror. Also, label the angle of incidence and angle of reflection on it.

There is a mistake in each of the following ray diagrams given as figures a, b, and c. Make the necessary correction (s).

(a)	(b)	(c)

Morning star is the name given to

Which of the following figures depicts the position of pole star correctly? 

Sun appears to move from east to west around the earth. This means that earth rotates from

Suppose a new planet is discovered between Uranus and Neptune. Its time period would be