Objective General Knowledge

Q. We observe twinkling of stars due to
1 constant change of refractive index of the medium between the stars and the Earth because of temperature variation
2 frequent and periodic fluctuation of temperature of the surface
3 great distance of stars from the Earth
4 rise and fall of gaseous ball of fire inside the stars
Ans: 1
Q. Global positioning system (GPS) is associated with
1. determining latitude and longitude
2. constellation of satellites
3. US system of GPS and Russian system of GLONASS
4. navigation
Select the correct answer using the code given below:
1 1 and 4 only
2 1, 2 and 4 only
3 2 and 3 only
4 1, 2, 3 and 4
Ans: 1
Q. Which one among the following statements is correct?
1 In winter season, the duration of day is more in northern hemisphere
2 In summer season, the duration of day is more in northern hemisphere
3 In summer season, the duration of day is less in northern hemisphere
4 In winter season, the duration of day is less in southern hemisphere
Ans: 2
Q. What is the similarity between Milwaukee Deep, Java Trench and Challenger Deep?
1 They are the deepest points of the Atlantic, Indian and Pacific Oceans, respectively
2 They all are trenches in the Pacific Ocean
3 They all are trenches in the Indian Ocean
4 They all are deeps of the Atlantic Ocean
Ans: 1
Q. A body initially at rest is acted upon by a constant force. The rate of change of its kinetic energy varies:
1 linearly with square of time.
2 linearly with square root of time.
3 linearly with time.
4 inversely with time.
Ans: 1
Q. 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 reflectors
4 Convex mirrors should be used as shaving
Ans: 1
Q. Light travels in optical fibre 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:
1 total internal reflection of light
2 diffraction of light
3 refraction of light
4 polarisation of light
Ans: 1
Q. 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.
Ans: 1
Q. 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 Air turbulence of earth's atmosphere
2 Poor optical polish achievable on large mirrors
3 Poor tracking capacities of telescopes
4 Varying density of air in the Earth's atmosphere
Ans: 1
Q. Bats can ascertain distances, directions, nature and size of the obstacles at night. This is possible by reflection of the emitted:
1 ultrasonic waves from the bat.
2 ultrasonic waves from the distant objects.
3 supersonic waves from the bat.
4 supersonic waves from the distant objects.
Ans: 1