Light, Shadows and Reflections quiz

Which of the following is a luminous object?

Butter paper is:

A shadow is formed when light is blocked by:

The image formed by a pinhole camera is:

Light travels in:

The colour of the shadow of a red rose is:

Which of the following is opaque?

We see the Moon because it:

Which of these changes the direction of light falling on it?

Shadows are shortest at:

Why can we not see objects in a completely dark room? (2 marks)

Give two examples each of transparent and translucent objects. (2 marks)

Why is the shadow of an object formed on the side opposite to the light source? (2 marks)

How does the size of a shadow change as the object moves closer to the light source? (2 marks)

Why does a pinhole camera form an inverted image? (2 marks)

Can a shadow show the colour of an object? Explain. (2 marks)

Why are shadows longer in the morning and evening? (2 marks)

How can a mirror be used to send a light signal? (2 marks)

Why do we see a solar eclipse? Explain using shadows. (2 marks)

Name two sources of light other than the Sun. (2 marks)

A pole 2 m tall casts a shadow of 3 m. At the same time, a building casts a shadow of 30 m. Find the height of the building. (3 marks)

Light takes about 8 minutes 20 seconds to reach the Earth from the Sun. Express this time in seconds. If light travels 3,00,000 km in a second, find the approximate distance of the Sun. (3 marks)

In a class activity, 20 objects were tested. 7 were transparent, 5 were translucent and the rest were opaque. How many were opaque? What percentage were opaque? (3 marks)

A girl's shadow is 1.2 m long at 10 a.m. and 0.4 m long at noon. By how much did it shorten? Express the noon shadow as a fraction of the 10 a.m. shadow. (3 marks)

A torch beam travels 6 m from the torch to a mirror and is reflected 4 m to a wall. Find the total distance travelled by the beam. If light travels 3,00,000 km per second, is the time taken noticeable to us? Explain. (3 marks)

Read the passage and answer the questions. During a power cut, children made animal shapes on the wall using their hands and a candle. When they moved their hands closer to the candle, the shadows became bigger. (i) What is needed to form these shadows? (ii) Why did the shadows become bigger when the hands moved closer to the candle? (iii) Why were the shadows dark even though the hands were brown? (5 marks)

Read the passage and answer the questions. Students made a pinhole camera using two boxes, one sliding inside the other. The smaller box had a screen of tracing paper. When they pointed it at a lit building, they saw an upside-down image on the screen. (i) Why was tracing paper used for the screen? (ii) Why was the image upside down? (iii) What does this activity prove about light? (5 marks)

Read the passage and answer the questions. Arjun's classroom has clear glass windows, frosted glass in the washroom and a wooden door. (i) Classify the three materials as transparent, translucent or opaque. (ii) Why is frosted glass used in the washroom? (iii) Which material will form the darkest shadow? (5 marks)

Read the passage and answer the questions. On a sunny day, Meena held a small mirror in the sunlight and turned it towards a wall. A bright patch of light appeared on the wall, and it moved when she tilted the mirror. (i) What happened to the sunlight that fell on the mirror? (ii) Why did the patch move when she tilted the mirror? (iii) Give one use of this property. (5 marks)

Read the passage and answer the questions. A long-distance runner noticed that her shadow was very long and in front of her when she ran towards the east in the evening. At noon, her shadow was very short. (i) Why was her shadow in front of her in the evening while running east? (ii) Why was it short at noon? (iii) In which direction would her shadow fall in the morning? (5 marks)

Describe an activity to classify materials as transparent, translucent and opaque using a torch. Draw diagrams of the light passing through each type and give three examples of each. (6 marks)

Draw a labelled diagram of a pinhole camera. Explain how it is made and how it forms an image. State two properties of the image formed. (6 marks)

Explain how shadows are formed, with a labelled diagram. Describe how the shape and size of a shadow change with the position of the object and the light source. (6 marks)

Describe the activity with a straight pipe and a bent pipe to show that light travels in a straight line. Draw diagrams for both cases and explain the observations. (6 marks)

Draw a diagram showing reflection of light from a plane mirror. Explain how a mirror forms an image, what lateral inversion is, and two uses of mirrors. Describe how two mirrors can help see objects behind you. (6 marks)