Physics Basics — Set 5
Physics · भौतिकी की मूल बातें · Questions 41–50 of 50
What is the SI unit of Resistance?
Correct Answer: D. Ohm
The Ohm is the SI unit of electrical resistance, named after Georg Simon Ohm. It measures how much a material opposes the flow of electric current. According to Ohm's Law, resistance is the ratio of voltage to current.
Who discovered the laws of electrolysis?
Correct Answer: A. Michael Faraday
Michael Faraday published the laws of electrolysis in 1834. These laws describe the relationship between the amount of substance produced and the electricity consumed. Faraday's work laid the foundation for modern electrochemistry and electromagnetism.
Which instrument is used to measure the humidity of the air?
Correct Answer: C. Hygrometer
A hygrometer is an instrument used to measure the amount of water vapor in the atmosphere. It is essential for weather forecasting and industrial processes requiring moisture control. There are several types, including hair tension and electronic hygrometers.
Which principle states that a body immersed in a fluid experiences an upward buoyant force?
Correct Answer: C. Archimedes' Principle
Archimedes' Principle states that the upward buoyant force on an object is equal to the weight of the fluid it displaces. This principle explains why objects float or sink in water. It is a fundamental law used in shipbuilding and fluid dynamics.
What is the SI unit of Force?
Correct Answer: C. Newton
The Newton is the SI unit of force, named in honor of Isaac Newton. It is defined as the force needed to accelerate one kilogram of mass at one meter per second squared. Force is a vector quantity having both magnitude and direction.
Who invented the first battery, known as the Voltaic Pile?
Correct Answer: A. Alessandro Volta
Alessandro Volta invented the first chemical battery, the Voltaic Pile, in 1800. This invention provided the first source of continuous electric current. The unit of electric potential, the Volt, is named after him.
Which instrument is used to measure the height of an aircraft above sea level?
Correct Answer: A. Altimeter
An altimeter is an instrument used to measure the altitude of an object above a fixed level. Most aircraft use pressure altimeters that calculate height based on atmospheric pressure. It is a crucial tool for navigation and flight safety.
What is the SI unit of Magnetic Flux?
Correct Answer: A. Weber
The Weber is the SI unit of magnetic flux, named after the German physicist Wilhelm Eduard Weber. One Weber is the amount of flux that produces one volt in a one-turn loop in one second. Magnetic flux density is measured in Teslas.
Which device is used to measure potential difference between two points in a circuit?
Correct Answer: B. Voltmeter
A voltmeter is an instrument used for measuring the electric potential difference between two points. It is always connected in parallel with the component being measured. Ideal voltmeters have infinite resistance to avoid affecting the circuit.
Who discovered the Neutron?
Correct Answer: D. James Chadwick
James Chadwick discovered the neutron in 1932, a particle with no charge in the atomic nucleus. This discovery was vital for the model of the atom and the development of nuclear energy. He was awarded the Nobel Prize in Physics in 1935.