M.M: 29 marks Date: 28/07/2011
Time: 40 minutes
Q 1: Fill in the blanks (1 mark per question x 11 = 11 marks)
- _________ objects do not allow light to pass through them.
- Light travels in a __________ line.
- Clear shadows are formed when an ________ object comes in the path of light.
- __________ objects allow light to pass through them partially.
- Objects having ability to produce their own light are called _____________ objects.
- The length of a shadow in daytime is smallest at _______ time.
- An image that cannot be obtained on a screen is called ___________ image.
- The left part of an object becomes _______ part when the object is seen in a plane mirror.
- An image formed at 2 m from the plane mirror will be _____ far from the object.
- The category of image formed in a cinema screen is ________.
- The category of image formed in standing clear water is ________.
Q 2: Choose the right answer: (1 mark)
A plane mirror forms an image which is:
- Inverted
- Real
- Enlarged
- Virtual
Q 3: Find the odd one out: (1 mark)
- Sun
- Stars
- Burning candle
- Moon
Q 4: What do you understand by rectilinear propagation of light? (1 mark)
Q 5: Why do we not see shadow of a plane flying very high in the sky? (1 mark)
Q 6: Write True or False, also write the correct statement wherever applicable for the false ones. (1 mark per question x 7 = 7 marks)
- A screen is not always needed for formation of a shadow - ________
- Shadows can never mislead about the shape of the object - _________
- Moon is an example of non-luminous object - _______________
- A firefly is a living source of light - _________
- The image formed by a pin hole camera is not inverted - __________
- Shadows and images are same - ___________
- Coating of mercury is done at the back of a glass to make it a mirror - ________
Q 7: With the help of an activity, prove that a plane mirror reflects light. (2 marks)
Q 8: In brief, describe the construction of a sliding pin hole camera with a diagram. (4 marks)
Q 9: Write two conditions that are necessary for an object to be visible to our eyes. (2 marks)
Q 10: What will happen if you try to see the flame of a burning candle through the following? (3 marks)
- Opaque object
- Translucent object
- Transparent object
Q 11: What is a periscope? Draw its diagram and explain its working in brief. (3 marks)
Q 12: Define light, shadow and reflection. (3 marks)