1.4. Mathematics Tools for Physics http://www.ck12.org
- How many base units are there?
- Why do we want the hours on top in the first conversion factor?
- What do measured numbers tell you?
- What is the purpose of significant figures?
Review
Questions
- Write the following numbers in proper scientific notation.
(a) 3,120
(b) 0.00000341 - Write the following numbers in expanded form.
(a) 4.35× 106
(b) 6.1× 10 −^4 - How many significant figures are in the following numbers?
(a) 2.3
(b) 17.95
(c) 9.89× 103
(d) 170
(e) 1.02 - Perform the following calculations and give your answer with the correct number of significant figures:
(a) 10.5 + 11.62
(b) 0.01223 + 1.01
(c) 19.85−0.0113 - Perform the following calculations and give your answer with the correct number of significant figures:
(a) 0.1886× 12
(b) 2.995÷0.16685
(c) 910×0.18945
- exponential notation: A method of writing or displaying numbers in terms of a decimal number between 1
and 10 multiplied by a power of 10. The scientific notation of 10,492, for example, is 1. 0492 × 104. - significant digits: The significant figures (also known as significant digits, and often shortened to sig figs) of
a number are those digits that carry meaning contributing to its precision. This includes all digitsexcept: - leading and trailing zeros which are merely placeholders to indicate the scale of the number.
- spurious digits introduced, for example, by calculations carried out to greater precision than that of the
original data, or measurements reported to a greater precision than the equipment supports.
Physics is the branch of science that primarily studies matter, energy, and their interactions. Using the scientific
method, physicists hypothesize relationships, design experiments, and complete tests to turn those hypotheses
into theories. Physicists around the world not only work from the same body of knowledge—the same laws and
theories—but they also use standard units and the SI system of measurement to ensure that the replication of their
experiments is possible. Physics is more than numbers and equations; it is about asking how and why things work
and questioning everything we see in the natural world.