Question: Suppose you are standing 1 m in front of a plane mirror. What should be the minimum vertical size of the mirror so that you can see your full image in it?
1. twice your height
2. 2m
3. 0.50 m
4. half of your height
Answer: 4
Question: The material used for electric fuse is an alloy of tin and lead. This alloy should have:
1. high specific resistance and high melting point
2. low specific resistance and low melting point
3. low specific resistance and high melting point
4. high specific resistance and low melting point
Answer: 4
Question: When a moving bus suddenly applies brakes, the passengers sitting in it fall in the forward direction. This can be explained by:
1. the theory of relativity
2. Newton’s third law
3. Newton’s second law
4. Newton’s first law
Answer: 4
Question: Bats can ascertain distances, directions, nature and size of the obstacles at night. This is possible by reflection of the emitted:
1. supersonic waves from the distant object
2. supersonic waves from the bat
3. ultrasonic waves from the distant objects
4. ultrasonic waves from the bat
Answer: 4
Question: Which one among the following is the major cause of blurring and unsharp images of objects observed through very large telescope at the extreme limit of magnification?
1. varying density of air in the Earth’s atmosphere
2. poor tracking capacities of telescopes
3. poor optical polish achievable on large mirrors
4. Air turbulence of earth’s atmosphere
Answer: 4
Question: A man is at rest in the middle of a horizontal plane of perfectly smooth surface of ice. He can move himself to the shore by making use of Newton’s:
1. Third law of motion
2. First law of motion
3. Second law of motion
4. First, second and third laws of motion.
Answer: 1
Question: Light travels in optical fiber irrespective of its shape because it is a device by which signals can be transferred from one location to another. It is based on the phenomenon of:
1. total internal reflection of light
2. diffraction of light
3. polarization of light
4. refraction of light
Answer: 1
Question: Which one among the following statements is correct?
1. Concave mirrors are used as reflectors
2. Convex mirrors are used by doctors to examine oral cavity
3. Convex mirrors are used as reflactors
4. Convex mirrors should be used for shaving
Answer: 1
Question: A jet plane files through air with a velocity of 2 Mach. While the velocity of sound is 332 m/s the air speed of the plane is:
1. 66.4 km/s
2. 166 m/s
3. 664 m/s
4. 332 m/s
Answer: 3
Question: When milk is churned, the cream separates from it due to:
1. Centrifugal forcce
2. Frictional force
3. Gravitational force
4. Viscous forces
Answer: 1