Sunday, March 28, 2021

Fun With the Casio fx-3650P (March 28 Edition)

Fun With the Casio fx-3650P (March 28 Edition)



Square Root Simplification



This program attempts to simplify the square root √D  to M√A, where D, M, and A are positive integers.



Program:  (68 bytes)

? → D : 2 →  M : Lbl 0 : D ÷ M ² → A : Fix 0 : Rnd : Ans →B : Norm 1 : A - B = 0 ⇒ Goto 1 : 1 M+  : M √ D ⇒ Goto 2 : Goto 0 : Lbl 2 : 1 → M : D →B : Lbl 1 : M ◢ B



Example:

D = 188.  Result:  M = 2, B = 47.   √188 = 2√47

D = 775.  Result:  M = 5, B = 31.   √775 = 5√31



Present Value of a Growing Annuity



Calculate the present value of an annuity where the payments grow X% of each period, where the Y% is the interest rate of the annuity.  


Variables:

A = PV

X = periodic growth rate, G%

Y = periodic interest rate, R%

B = payment

C = number of periods, N



Programs:  (77 steps)

? → B : ? → X : ? → Y : ? → C : 0 → A : 1 → M : Lbl 0 : A + ( 1 + .01 X ) ^ ( M - 1 ) ÷ ( 1 + .01 Y ) ^ M → A : 1 M+ : M > C ⇒ Goto 1 : Goto 0 : Lbl 1 : A B → A


Examples:



1.  B = 1000.00 (PMT), X = 3 (G%), Y = 5  (R%), C = 10

Result:  A = 8747.596154 ($8,747.60)



2.  B = 1000.00, X = 8, Y = 5, C = 10

Result:  A = 10846.42231  ($10,846.42)



Smoke:  Front Velocity and Time for a Corridor to Fill


This program estimates:

*  The front velocity of the smoke (how quickly the smoke fills a corridor)

*  The time it takes for smoke to fill the corridor.



The program uses SI units (meters, seconds, kilograms).  



Program:  (44 bytes)

? → A : ? → B : ? → Y : ? → X : √ ( 9.80665 Y ( 1 - A ÷ B ) ) ÷ 2 → C  ◢ X ÷ C → D


Variables:


Inputs:

A: Ambient Temperature, °C

B:  Gas Temperature, °C

Y:  Height, m

X:  Length, m


Outputs:

C:  Velocity, m/s

D:  Time, s



Example:

Inputs:

A: Ambient Temperature = 28°C

B:  Gas Temperature = 38°C

Y:  Height = 2.95 m

X:  Length = 4.18 m



Results:

C:  Velocity = 1.379588456 m/s

D:  Time = 3.029889081 s



Source:

Lawson, J.R. and Quintiere, J.G. "Slide Rule Estimates of Fire Growth".  Fire Technology, Vol 21., No. 4, November 1985, pg. 267



Sailing:  Distance by Bearings


This program calculates the distance off the abeam for either one or two bearings on the bow.  The variable C is the choice variable.  For one bearing, enter 1 for C.  For two bearings, enter 2 for C.  The fx-3650P is set to Degrees mode. 



Distance Using One Bearing

D = X * sin A / cos A = X * tan A

A = angle off the bow, X = run,  D = distance off the abeam



Distance Using Two Bearings

D = (X * sin A) / (sin abs(A - B))

A = first angle, B = second angle



Program: (60 bytes)

Deg : ? → C : ? → X : ? → A : C = 2 ⇒ Goto 2 : X tan A → D : Goto 3 : Lbl 2 : ? → B : √ ( ( A - B ) ² ) : X sin A ÷ sin Ans → D : Lbl 3 : D


 Example:


1 Angle:   X = 150 ft, A = 15°.   Enter 1 for C.   Result:  D = 40.192378886 ft



2 Angles:  X = 150 ft, A (first) = 15°, B (second) = 19°.  Enter 2 for C.  Result:  D = 556.5484418 ft


Source:

Shufeldt, Henry H. and Newcomer, Kenneth E.   The Calculator Afloat:  A Mariner's Guide to the Electronic Calculator  United States Naval Institute.  Annapolis, Maryland. 1980.



Eddie 


All original content copyright, © 2011-2021.  Edward Shore.   Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited.  This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author.


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