Solving Physics Problems with your TI 83 Calculator
By David Doty

This web site is designed to help students become familiar with the use of the TI 83 and TI 83+ calculators for use in physics classes. While the use of this web page is not limited to physics students, the concepts addressed here tend to cause problems facing physics students.

How to input scientific notation with your TI


Addition and subtraction


Multiplication


Division

Sample physics problems

TI order of operations

Inputting using parentheses
Rationale

How to input scientific notation with your TI

The use of the [EE] key.


For many calculators, including the TI –83 and TI 83 Plus, the [EE] button is used to enter scientific notation. The [EE] button can be found in yellow above the comma key [,]. For entering scientific notation, the following keystrokes should be used: first type the number, then the 2nd key followed by the comma key, [2nd] [,] [EE], followed by the exponent. As an example, to enter 3 x 108 type [3] [EE] [8]. The display will read 3E8.

The calculator can be set to display answers in scientific notation or normal display. To set the display, simply press the mode button and using the arrow keys select the desired display and press enter. To leave this menu, press [2nd] [MODE] to quit.

Follow these examples for inputting basic addition, subtraction, multiplication, and division.


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Addition:


Add: 8.1 x 106 + 4.2 x 105
Type: 8.1 [EE] 6 [+] 4.2 [EE] 5
Displayed answer: 8.52E6
Numerical answer: 8.52 x 106 = 8,520,000


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Subtraction


Subtract: 6.2 x 10-3 – 2.8 x 10-4
Type: 6.2 [EE] -3 [–] 2.8 [EE] -4
Displayed answer: 5.92E-3
Numerical answer: 5 x 10-3 = 0.00592


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Multiplication


Multiply: (3 x 106) (2 x 103)
Type: 3 [EE] 6 [X] 2 [EE] 3
Displayed answer: 6E9
Numerical answer: 6 x 109 = 6,000,000,000


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Division


Divide:
Type: 6 [EE] 8 [/] 2 [EE] 10
Displayed answer: 3E-2
Numerical answer: 3 x 10-2 = 0.03


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Sample Physics Problems


1) What is the magnitude of the gravitational force between an electron and a proton separated by a distance of 1.0 x 10-10 meters? answer
2) A positive charge of 6.0 x 10-6 C is 0.030 m from a second positive charge of 3.0 x 10-6 C. Calculate the electric force between the charges. answer
3) In a vacuum, the wavelength of green light is 5 x 10-7 meter. What is its frequency? answer
4) What is the energy of a photon with a frequency of 3.00 x 1013 cycles per second? answer


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Answers to Sample Physics Problems


1) Calculate gravitational force via Newton's Universal Law of Gravitation



Type: 6.67 [EE] -11 [X] 9.11 [EE] -31 [X] 1.67 [EE] -27 [/] 1 [EE] -10 [^2]
Calculator Display: 6.67E-11 * 9.11E-31 * 1.67E-27 / 1E-10^2
Displayed answer: 1.0E-47
Numerical answer: 1.0 x 10-47

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Back to Problems


2) Calculate Coulomb Force via Coulomb's Law:



Type in: 8.99 [EE] 9 [X] 6.0 [EE] -6 [X] 3.0 [EE] -6 [/] .030 [^2]
Calculator Display: 8.99E9 * 6.00E-6 * 3.00E-6 / .030^2
Displayed answer: 179.8
Numerical answer: 179.8


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Back to Problems

3) Frequency given speed and wavelength:


Type in: 3 [EE] 8 [/] 5 [EE] -7
Calculator display: 3E8/5E-7
Displayed answer: 6E14
Numerical answer: 6.0 x 1014

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Back to Problems


4) Energy given frequency and Planck's constant:


Type in: 6.63EE-34 X 3EE13
Calculator display: 6.63E34 * 3E13
Displayed answer: 1.99E-20
Numerical answer: 1.99 x 10-20


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Back to Problems


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Inputting using parentheses


For those of you who do not want to use the EE button on the calculator, yes parentheses can be used to enter equations.
Example from the division section above:
Divide:
This can be entered: (6 [X] 10 [^] 8) [/] (2 [X] 10 [^] 10)
Displayed answer: 3E-2
Numerical answer: 3 x 10-2 = 0.03


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TI orders of operation


The problem with typing in [X] 10 [^] (exponent) is that the TI 83 calculators do not distinguish scientific notation from multiplication and division. This becomes problematic when dividing numbers in scientific notation. As an example look at question 3 from the sample physics problems.
In a vacuum, the wavelength of green light is 5 X 10-7 meter. What is its frequency?


The solution is:

However if a student mistakenly types in:
3 [X] 10 [^] 8 [/] 5 [X] 10 [^] -7
the TI gives the answer of 6.
This is the orders of operations that the TI follows for this example:

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Rationale


Although one of the goals of the new NYS standards is to increase conceptual understanding of physics, students still need to be able to mathematically solve physics problems. Many students use the Texas Instrument calculators (TI 83 and TI 83+) as a tool for solving problems and we need to clarify the problems that students have in using this tool. The TI calculators do not use common sense when performing calculations, so the students need to correctly input the data to get the correct outcomes.

This web page addressed requirements for PHY690: Masters' Project at SUNY - Buffalo State College. Dr. Dan MacIsaac contributed considerably to this work.


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David Doty


David Doty is currently teaching NYS Regents Physics, Environmental Science, and various science laboratories at Salamanca City Central Schools. He has a Bachelor of Arts in Mathematics from the State University of New York at Buffalo and is working on the completion of his Masters in Physics Education at Buffalo State College.


If you wish to contact David, please e-mail ddoty@salamancany.org