346: If the stars are seen to rise perpendicular to the horizon by an observer, he is located on the
(a) Equator
(b) Tropic of Cancer
(c) South Pole
(d) North Pole
347: What is the role of ultraviolet (UV) radiation in the water purification systems?
1. It inactivates/kills the harmful micro-organism in water.
2. It removes all the undesirable odours from the water.
3. It quickens the sedimentation of solid particles, removes turbidity and improves the clarity of water.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
348: What explains the eastward flow of the equatorial counter-current?
(a) The Earth's rotation on its axis
(b) Convergence of the two equatorial currents
(c) Difference in salinity of water
(d) Occurrence of the belt of calm near the equator
349: Amit started a business by investing Rs. 30,000. Rahul joined the business after some time and invested Rs. 20,000. At the end of the year, profit was divided in the ratio of 2 : 1. After how many months did Rahul joined the business?
(a) 2
(b) 3
(c) 4
(d) 5
350: A person sitting in a bus experiences a jerk, when the bus stops all of a sudden. This is due to:
(a) Law of inertia
(b) Newton's third law of motion
(c) Einstein's law of relativity
(d) None of these