Quick Review of the 10’s places 123,456 1’s place 10’s place 100’s place 1,000’s place...
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Quick Review of the 10’s places 123,456 1’s place 10’s place 100’s place 1,000’s place 10,000’s place 100,000’s place
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Transcript of Quick Review of the 10’s places 123,456 1’s place 10’s place 100’s place 1,000’s place...
Quick Review of the 10’s places
123,4561’s place
10’s place
100’s place
1,000’s place10,000’s place
100,000’s place
Quick Review of the 10’s places
0.1234
10ths place
100ths place
1,000ths place
10,000ths place
HOW TO MEASURE IN SCIENCE
The measurement you make depends on the instrument
The the more precise the instrument, the more precise the measurement and more SIG FIGS
10 cm 20 cm 10 cm 20 cm
Which ruler is more precise????
HOW TO MEASURE IN SCIENCE
The first rule of measuring, you always guess ONCE
10 cm 20 cm0 cm
But how?
Look at the increments (lines), you know that the object is between 10 and 20 cm.
OBJECT
10 cm 20 cm0 cm
OBJECT
YOU KNOW the object is: 1 cm
A good guess would be 16 cm or 17 cm or 18 cm.
guess goes here
(notice that the guess is one 10’s place smaller than the increments)
200 cm 300 cm100 cm
OBJECT
YOU KNOW the object is:
Good answers are 220, 230, 240
guess goes here
(notice that the guess is one 10’s place smaller than the increments)
Pay attention to scale
2 cm
200 cm 300 cm100 cm
OBJECT
Remember from before, how do we know the 3 is the guess digit?
Pay attention to scale
230 cm
200 cm 300 cm100 cm
OBJECT
(notice that the guess is one 10’s place smaller than the increments)
Pay attention to scale
230 cm = good23 cm = bad
235 cm = badWHY?
10 cm 20 cm0 cm
A good measurement would be:
Which digit is my guess
What place is it in?
1 cm or 2 cm or 3 cm.
10 cm 20 cm0 cm
is 2.1 cm , OK?
is 2.0 cm , OK?
2 cm is good?
20 cm 30 cm10 cm
OBJECT
Let’s use the more precise ruler
What do we know??
Now let’s guess.
A quick trick is to look the smallest lines and decide what 10’s place is changing. Your guess will be a 10’s place smaller. ALWAYS
23 cm
23.6 cm
YOU TRY
200 cm
300 cm
100 cm
OBJECT
200 cm
300 cm
100 cm
Find the 10’s place changing between the smallest increments and make sure your guess is a 10’s place smaller (to the right)
OBJECT
180 cm, 190 cm
182 cm, 183 cm, etc…
2 cm and 2.0 cm are not the same in SCIENCE
10 cm0 cm
0 cm 10 cm
2 cm means:
About 1,2, or 3 cm
The last SIG FIG in a measurement is always assumed to be a guess
2.0 cm means:
About 1.9, 2.0, or 2.1 cm
Even in a digital scale, there is a guess.
If the object happens to line up “exactly” with an increment, you will have to add zeroes to make sure the guess is in the right place.
200 cm 300 cm100 cm
OBJECT
178 cm
200 cm 300 cm100 cm
OBJECT
180 cm
200 cm 300 cm100 cm
OBJECT
200 cm
Which ruler would be read correctly 42 cm
100 cm0 cm
0 cm 100 cm
40 cm 50 cm
40 cm
42 cm
42.0 cm
0 cm 1 cm
0 cm 1 cm
0 cm 1 cm
Some harder ones...
Look at the place changing in the smallest increment...
.52 cm, .53 cm etc…
.03 cm, .04 cm etc…
.30 cm (or .29 or .31)
All Instruments are read this way. Even if they look different.
They are read with one estimated digit
Liquid instrument like graduated cylinders are read at the bottom of the meniscus
10 mL
20 mL
What would be a good reading?? Don’t forget the unit.
Some have numbers that increase from the bottom up. They tell you how much liquid is in them.
0 mL
Some have numbers that increase from the top down. They tell you how much liquid you have taken from them.
10 mL
0 mL
20 mL
10 mL
0 mL
20 mL
Start End
1 L
0 L
10 dL
20 dL
0 dL
30 cm3
20 cm3
40 cm3
0 10 20 4030 80706050 100 g90
0 100 200 400300 500 g
0 1 2 43 8765 10 g9
Triple Beam Balance
Just add up the values for each pointer
The most precise increments are changing by 10ths or .1 gSo your guess will be a 10’s place smaller 100ths or .0X g
A good reading would be: 40 + 200 + 3.32 g243.32 gCentigram balance
0 10 20 4030 80706050 100 g90
0 100 200 400300 500 g
0 1 2 43 8765 10 g9
Triple Beam Balance
0 + 0 + 2.56 g2.56 g
0 10 20 4030 80706050 100 g90
0 100 200 400300 500 g
0 1 2 43 8765 10 g9
Triple Beam Balance
0 + 0 + 1.50 g1.50 g
0 10 20 4030 80706050 100 g90
0 100 200 400300 500 g
0 1 2 43 8765 10 g9
Triple Beam Balance
0 + 0 + 4.00 g4.00 g
0 10 20 4030 80706050 100 g90
0 100 200 400300 500 g
0 1 2 43 8765 10 g9
Triple Beam Balance
0 + 0 + 0.04 g0.04 g
The guess is always in the 100th place!!!
The 100 m dash records for the last century. Why did the vertical lines get smaller?
