# 1.01 Numbers and Units

A complete measurement is called a PHYSICAL QUANTITY: It contains a number and a unit.

Whenever you do a calculation you include number and unit in the calculation. First solve the number part, then solve the unit part.

EXAMPLE

A car has driven a distance of 30 km. It took the car 3 hours. Calculate the average speed of the car.

= 10 km/h

WORKING WITH POWERS

SCIENTIFIC NOTATION :Rewrite the number into a number that fits between 1-10 and a power.

How to rewrite 350 into scientific notation

First get the number part and then do the power part. The number should be 3,5

The original number is larger than the power number so therefore the power is positive. The amount of times I have to replace the comma to go from 3,5 until 350 is 2 times so the power is 102

How to rewrite 0,0035 into scientific notation

First get the number part and then do the power part. The number should be 3,5

The original number is smaller than the power number so therefore the power is negative. The amount of times I have to replace the comma to go from 3,5 until 0,0035 is 3 times so the power is 10-3

For additional exercises about scientific notation use the following link:

https://www.mathgames.com/skill/8.22-convert-between-standard-and-scientific-notation

https://eu.ixl.com/math/grade-11/convert-between-standard-and-scientific-notation (this is the better one, but you have to get a free membership)