NIOS Class 12 Physics Chapter 1 – Units, Dimensions, and Vectors
Units, Dimensions, and Vectors
Multiple-Choice Questions – Answers
Q: The dimensional formula for mass is:
Answer: [MLT⁻¹]
Q: The unit of time is:
Answer: Second
Q: A light-year is the unit of which physical quantity?
Answer: Distance
Q: The dimensional formula for pressure is:
Answer: [MLT⁻²]
Q: What is the dimensional formula for the coefficient of viscosity?
Answer: [MLT⁻¹]
Short-Answer Questions
Q: A light-year is the unit of which physical quantity?
Answer: A light-year is the unit of distance.
Q: Write the dimensions of force.
Answer: The product of mass and acceleration is called force.
Dimensional formula for force:
Force = Mass × Acceleration F = M × [LT⁻²] F = [MLT⁻²]
Q: What do you understand by a ‘unit’?
Answer: To determine the measurement of any physical quantity, a fixed value of that quantity is adopted as a standard. This standard is known as a ‘unit’.
