# Physics GK Questions and Answers

#### Overview:

 Questions and Answers Type: MCQ (Multiple Choice Questions). Main Topic: General Knowledge. General Knowledge Sub-topic: Physics. Number of Questions: 5 Questions with Answers.

##### 1. What is the minimum escape velocity of rocket to be launched into space?

1. 7.5 Km/Sec
2. 8.2 Km/Sec
3. 10.1 Km/Sec
4. 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?

1. Carbon dioxide
2. Carbon monoxide
3. Ozone
4. 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?

1. CT Scan
2. X-Ray Scan
3. Ultrasound Scan
4. 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 -

1. Nuclear fusion
2. Nuclear fission
3. Radioactivity
4. 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?

1. Hydrometer
2. Hygrometer
3. Barometer
4. Lactometer

Answer: (b) Hygrometer

Solution: A hygrometer is an instrument that measures and records the relative humidity of the air.