Directions: In the following physics general knowledge questions, four answers are given, and only one answer is correct. Read the questions and choose the correct answers. If you want to check the answer, click on the answer button and know the correct answer with an explanation.
1. What is the minimum escape velocity of rocket to be launched into space?
7.5 Km/Sec
8.2 Km/Sec
10.1 Km/Sec
11.2 Km/Sec
Answer: (d) 11.2 Km/Sec
Solution: In physics, escape velocity is the speed at which the kinetic energy plus the gravitational potential energy of an object is zero. From the surface of the Earth, the escape velocity is about 11.2 Km/Sec, which is approximately 34 times the speed of sound.
2. What stops the ultraviolet radiation of the Sun to reach the earth?
Carbon dioxide
Carbon monoxide
Ozone
Ammonia
Answer: (c) Ozone
Solution: The ozone layer prevents the harmful ultraviolet radiation of the sun to reach the earth.
3. Optic fibres are mainly used for which of the following?
CT Scan
X-Ray Scan
Ultrasound Scan
Endoscopy
Answer: (d) Endoscopy
Solution: The optical fibre is used in endoscopic instruments that enable doctors to view internal body parts without having to perform surgery. An endoscope uses fibre optics, which allow for the effective transmitting of light.
4. Energy is continuously generated in the sun due to -
Nuclear fusion
Nuclear fission
Radioactivity
Electrons
Answer: (a) Nuclear fusion
Solution: The central mass of the sun becomes increasingly hot and dense, eventually initiating thermonuclear fusion in its core. Nuclear fusion is a nuclear reaction in which two or more atomic nuclei join together to form a single heavier nucleus, and energy is released. Nuclear fusion is the process that powers active stars.
5. Which instrument measures and records the relative humidity of air?
Hydrometer
Hygrometer
Barometer
Lactometer
Answer: (b) Hygrometer
Solution: A hygrometer is an instrument that measures and records the relative humidity of the air.