82 Chapter 4: Constants and Measurement Units
04UNITSDOC TI
-
89/92Plus:Constants and Measurement Units (English) SusanGullord Revised:02/23/01 10:54 AM Printed:02/23/01 2:12 PM Page82 of 12
Steps
³
TI-89
Keystrokes
›
TI-92 Plus
Keystrokes Display
1. Display the
MODE dialog box,
Page 3. For Unit System mode,
select SI for the metric system of
measurements.
Results are displayed according to
these default units.
3…B1
¸
3…B1
¸
2. Create an acceleration unit for
meters/second2 named _ms2.
The UNITS dialog box lets you select
units from an alphabetical list of
categories. You can use
2D
and
2C
to scroll one page at a time
through the categories.
Now, instead of re-entering
_m/_sñ
each time you need it, you can use
_ms2
.
Also, you can now use the UNITS
dialog box to select
_ms2
from the
Acceleration
category.
29DBM
¸
e29
DDDBS
¸
Z2§
¥
2™MS
j2¸
¥9DBM
¸
e¥9
DDDBS
¸
Z2§
2
MS
2¸
3. Calculate the force when
m = 5 kilograms (_kg) and
a = 20 meters/second2 (_ms2).
If you know the abbreviation for a
unit, you can type it from the
keyboard.
5¥
2™KG
jp20
¥2™
MSj2
¸
52
KG
p20
2
MS2
¸
4. Using the same m, calculate the
force for an acceleration due to
gravity (the constant _g).
For
_g
, you can use the pre-defined
constant available from the UNITS
dialog box or you can type
_g
.
5¥
2™KG
jp
29B
jG
¸¸
52
KG
p
¥9B
G
¸¸
5. Convert to kilograms of force
(_kgf).
2
displays the
4
conversion
operator.
B2¥
2™KGF
j¸
B22
KGF
¸
Preview of Constants and Measurement Units
Using the equation f = mùa, calculate the force when m = 5 kilograms and a = 20
meters/secondñ. What is the force when a = 9.8 meters/secondñ. (This is the
acceleration due to gravity, which is a constant named _g). Convert the result from
newtons to kilograms of force.
If you use the UNITS
dialog box to select a
unit, the _ is entered
automatically.