1. Excess deepness
2. Reflection of sky and scattering of light by the drops of water
3. Blue colour of water
4. Upper layer of water
Option “2” is correct. “The ocean looks blue because red, orange and yellow (long wavelength light) are absorbed more strongly by water than is blue (short wavelength light). So when white light from the sun enters the ocean, it is mostly the blue that gets returned.
442. Who invented PlayStation?
1. Wright brothers
2. Reynold B. Johnson
3. Assen Jordanoff
4. Ken Kutaragi
Option “4” is correct. PlayStation was the brainchild of Ken Kutaragi, a Sony executive who had just finished managing one of the company’s hardware engineering divisions at that time and would later be dubbed as “The Father of the PlayStation”.
443. Instrument for measuring light intensity is called-
Option “1” is correct. Lucimeter is an instrument used for measuring light intensity.
444. Which one among the following is not an electro-magnetic wave?
1. X-Ray
2. Radio waves
3. Cathode Ray
4. Infrared Ray
Option “3” is correct. Electromagnetic radiation refers to the waves of the electromagnetic field, propagating through space-time, carrying electromagnetic radiant energy. It includes radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.
445. Which one of the following is a good electrical conductor?
1. Graphite
2. Diamond
3. Peat
4. Charcoal
Option “1” is correct. Graphite is a very good conductor of electricity due to the mobility of the electrons in its outer valence shells.
446. Which of the following pair is incorrect?
1. Hygrometer – Water vapour content of the atmosphere
2. Lactometer – Specific gravity of liquids
3. Anemometer – Speed of the wind
4. Seismograph – Earthquakes
Option “2” is correct. A lactometer is an instrument used to check purity of milk.
447. If a body is moving on a circular path, what is its average velocity if it completes one cycle in one second?
1. Average velocity depends upon time taken to complete one cycle
2. One
3. Zero
4. Average velocity is same as average speed
Option “3” is correct. Average velocity= Displacement/Total time taken since displacement=0 so average velocity=0
448. Why does a fountain pen leak in aeroplane flying at a height?
1. Because of reduced viscosity of the ink in the pen
2. Because of increased viscosity of the ink in the pen
3. Because of higher atmospheric pressure outside the pen
4. Because of lower atmospheric pressure outside the pen
Option “4” is correct. The atmospheric pressure decreases with altitude because gas molecules which make up the air concentrate near lower altitude in response to Earth’s gravity. Hence, air pressure is low at higher altitudes. Due to this difference in air pressure, the air inside the pen forces the ink to come out.
449. Instrument for measuring wind velocity is called –
Option “1” is correct. Rakesh Sharma was the first Indian to travel in Space. He was born on 13th January 1949 in Punjab, India. He flew to the Salyut 7 Space Station.
