PHYSICS; CLASS - VII
NAME: _________________________Date: 26 – 02 – 10 (1st sit) Roll. No. ___________F.M:75
SECTION A (Answer all questions)
QUESTION - 1.Fill in the blanks.(5)
i) Making one complete round of a circular path of radius r, the net displacement is ___________________. ii) If a body is dropped from a certain height, its velocity increases due to __________. iii) The force of friction is always equal and opposite to ____________ iv) An _______________ barometer has no liquids in it. v) If we fill a can having two holes at different heights with water, the water will flow out with a greater force from the _________ hole. vi) When the ray of light does not reach an object physically the image is a __________ image.
QUESTION - 2State whether the following statements are True or False.(5)
i) The unit of frequency is 1 / second.
ii) We fill an increase in pressure on us as we go up in hill. iii) The moon is a natural source of light.
iv) The image formed by a plane mirror can be easily obtained on a screen. v) When the height of the liquid column in a tall jar is doubled, the pressure at the bottom also gets doubled. QUESTION - 3Answer the following questions. (2 x 8)
i) Differentiate between noise and musical sound.
ii) Explain multiple reflections.
iii) Write two different uses of concave and convex mirror. iv) Write two applications of atmospheric pressure.
v) Explain uniform motion. What happens to the acceleration when a body travels in uniform motion? vi) Write different methods in which Permanent magnets can be made. vii) Define 1 bar?
viii) What is meant by the focal length of a lens?
QUESTION - 4Answer in one word.(4)
i) Air exerts more pressure in which direction?
ii) To convert oF to oC we use...