TI-95 PROCALC Programs
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Volume and Surface Area of a Cylinder
volume = π * r^2 * h
surface area = 2 * π * r * (h + r)
Program name: CYL (064 bytes)
‘RADIUS?’ BRK STO R
x^2 * ‘HEIGHT?’ BRK STO H
* PI = STO V ‘VOL=’ COL 16 MRG V BRK
2 * PI * RCL R * (RCL R + RCL H ) = STO A
‘AREA=’ COL 16 MRG A HLT
Example:
Example 1: RADIUS = 18.88, HEIGHT = 19.09
Result: VOL= 21377.64107, AREA= 4504.249671
Example 2: RADIUS = 17, HEIGHT = 9
Result: VOL= 8171.282492, AREA= 2777.167906
Engine Displacement of a Single Cylinder (automobile engine)
displacement = π ÷ 4 * bore^2 * stroke
Program: DSP (32 bytes)
‘BORE?’ BRK x^2 *
‘STROKE?’ BRK * PI / 4 =
‘DISP=’ COL 16 MRG = HLT
Example:
Example 1: BORE = 3.5 in; STROKE = 1.9 in
Result: DISP = 18.28014225 in^3
Example 2: BORE = 3 in; STROKE = 2.4 in
Result: DISP = 16.96460033 in^3
Magnetic Force
F = I * B * L * sin(Θ)
I: current in amps
B: density in Telsa
L: length of the conductor in meters
Θ: angle of the field in degrees
F: magnetic force in Newtons
Program: MGF (32 bytes)
INV DRG ‘ANGLE?’ BRK SIN *
‘L?’ BRK * ‘B?’ BRK * ‘I?’ BRK =
‘F=’ COL 16 MRG = HLT
Examples:
Example 1: Θ: 30°, L: 1.2 m, B: 0.7 T, I: 4 A
Result: F: 1.68 N
Example 2: Θ: 24°, L: 1.8 m, B: 0.7 T, I: 4.4 A
Result: F: 2.254947949 N
Note: INV DRG sets Degree mode
Signal to Noise Ratio
This program calculates signal to noise ratio based on the units used:
Decibels: SNR = S – N
Watts: SNR = 20 * log(S ÷ N)
Voltage: SNR = 10 * log(S ÷ N)
Program: SNR (120 bytes)
‘SIGNAL-NOISE’ PAU CLR
‘S?’ BRK STO S
‘N?’ BRK STO N
‘UNITS?’
DFN F1:DB @ 01
DFN F2: W @ 02
DFN F3: V @ 03
HLT
LBL 01 RCL S – RCL N = GTL 00
LBL 02 ( RCL S / RCL N ) LOG * 20 = GTL 00
LBL 03 ( RCL S / RCL N ) LOG * 10 = GTL 00
LBL 00 ‘SNR=’ COL 16 MRG = DFN CLR HLT
Notes:
Function labels have three characters, add spaces when necessary.
The colon and at sign are added automatically.
Examples:
Example 1: S: -20 db, N: -70 db
Result: SNR = 50
Example 2: S: 128 W, N: 25 W
Result: SNR = 14.18539922
Example 3: S: 76 V, N: 3.5 V
Result: SNR = 13.36745548
Eddie
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