Chapter 1:

Nature of Physics

Ch. 1 Learning Targets:

I can: estimate values using metric measurements

identify variables in an experiment

determine the relationship between variables from data or a graph

construct a high quality graph from a set of data

values using scientific notation

calculate and express values in the proper amount of significant figures

derive a literal equation for any variable

calculate and express the slope of a line

Vocabulary

dependent variable: a variable whose value depends on that of another

independent variable: a variable whose value does not depend on another

-relationships

direct: the variables do the same thing

inverse: an increase in one variable causes the decrease of the other

linear: the variables do the same thing

significant figure:the number of important single digits in the coefficent of an expression

accuracy:the extent to which a given measurement agrees with the standard value for the measurement

precision:the quality, condition, or fact of being true

Practice Problem 1

1) Paul stands at the rim of the Grand Canyon and yodels down to the bottom. He hears his yodel echo back from the canyon floor 5.20 s later. Assume that the speed of sound in air is 340 m/s. how deep is the canyon?


Given: change in time=5.2 s

V=340 m/s

change in x=?


Solve: v= change in x/change in time

5.2 x 340= (change in x/ 5.2) x 5.2

5.2 x 340= change in x

1,768= change in x x 2

change in x= 884m

Practice Problem 8

A torpedo fired from a submerged submarine is propelled through the water at 20.00 m/s and exploded upon impact with a target 2000 m away. If the sound of the impact is heard 101.4 s after the torpedo was fired, what is the speed of sound in water. (water resistance is neglected)


Given: t=101.4s


Solve: v= change in x/ change in time

change in time= change in x/velocity= 2000/20

change in time=100s

  • v=change in x/ change in time
2000/101.4 x 100 2000/1.4 = 1,429 m/s

v = 1,429 m/s


Formulas

S.N x 10^n

5 x 10^2

= 500


y=mx+b

m=slope of a line

b= y-intercept

y=1/5x+2

Relationships

Unit Questions

  • 1m=100cm, 1cm=100mm
  • if you had to pay $2.00 every time you came into the school, the amount of times you come into the school is the independent variable and the amount of money you pay is the dependent variable
  • scientific notation: 5.6x10^-9 = 0.0000000056.

Main Ideas

Nature of Science: key principles and ideas which provide a description of science as a way of knowing, as well as characteristics of scientific knowledge


Process of Testing a Hypothesis: you use scientific method which is a 5 step procedure that gives you the end results


The RelationshipBetween Variables in an Experiment: the independent variable is what you change and the dependent variable is the result of the change. They interact because one depends on the other