Concept explainers
Under what circumstances is it acceptable to omit the units during a physics calculation and advantage of using SI units in all calculations?
Answer to Problem 1QAP
When all the values are converted into SI units, it is acceptable to omit the units during physics calculations. And advantage of using SI units in calculation is it minimizes the errors in the calculation and eventually final answer will also be in SI units.
Explanation of Solution
Introduction:
Units are used to express the numerical value of a dimension. Any physical quantity has a dimension. Common physical quantities that we use are mass, length and time. Mass, length and time are considered as fundamental dimensions as they cannot be expressed in terms of other fundamental quantities. Dimension of many quantities are made of fundamental dimensions. For example, speed has the dimension of distance per unit time. In any equation the dimensions must be the same on both sides.
Since the dimensions of the both sides of the equation should be the same, it's a good idea to include the units of every measurement in each and every step. Thereby we can check whether the equation and the calculation are correct. And when all the values are converted into SI units, it is acceptable to omit the units during physics calculations. And it also minimizes the errors in the calculation and eventually final answer will also be in SI units.
Conclusion:
When all the values are converted into SI units, it is acceptable to omit the units during physics calculations. And advantage of using SI units in calculation is it minimizes the errors in the calculation and eventually final answer will also be in SI units.
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Chapter 2 Solutions
COLLEGE PHYSICS,VOLUME 1
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