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Variable velocity exercise #2

Estimating variable velocity with a computer model

Let's write a script that approximates the graphic procedure that I described earlier.

Please copy the code from Listing 2 into an html file and open the file in your browser.

Listing 2 . Variable velocity exercise #2.
<!---------------- File JavaScript2.html ---------------------><html><body><script language="JavaScript1.3">document.write("Start Script</br>"); //Declare and initialize constantsvar g = -32.2;//acceleration of gravity in ft/sec/sec var v0 = 100;//initial velocity in ft/secvar h0 = 6;//initial height in feet var tInc = 0.25;//calculation interval in seconds//Declare and initialize working variables var t = .0001;//current time in secondsvar h = h0;//current height in feet var v = 0;//current velocity in feet/secvar oldT = 0;//previous time in seconds var delT = 0;//change in time in secondsvar oldH = h0;//previous height in feet var delH = 0;//change in height in feet//The following variable is used to insert spaces in // the output display.var sp = "&nbsp;&nbsp;&nbsp;&nbsp;" //Compute and display various values for as long as the// height of the projectile is above the ground. while(h>0){ //This is the general equation for the height of a// projectile under the influence of gravity in a // vacuum.h = h0 + v0*t +0.5*g*t*t; //Compute and save the time interval since the// previous estimate of height, etc. delT = t-oldT;oldT = t;//Save the current time for the next iteration //Estimate the velocity based on the change in// height since the previous estimate. delH = h-oldH;v = delH/delT;//compute velocity oldH = h;//Save the current height for the next iteration.//Display the information for this iteration document.write("t = " + t.toFixed(2) + " seconds" + sp +" h = " + h.toFixed(1) + " feet" + sp + " v = " + v.toFixed(2) + " feet/second" + sp +"</br>"); //Increment the time for the next iteration.t = t + tInc; }//end while loopdocument.write("End Script");</script></body></html>

Screen output

The text shown in Figure 6 should appear in your browser window when the html file opens in your browser.

Figure 6 . Screen output for Listing #2.
Start Script t = 0.00 seconds h = 6.0 feet v = 100.00 feet/secondt = 0.25 seconds h = 30.0 feet v = 95.97 feet/second t = 0.50 seconds h = 52.0 feet v = 87.92 feet/secondt = 0.75 seconds h = 72.0 feet v = 79.87 feet/second t = 1.00 seconds h = 89.9 feet v = 71.82 feet/secondt = 1.25 seconds h = 105.8 feet v = 63.77 feet/second t = 1.50 seconds h = 119.8 feet v = 55.72 feet/secondt = 1.75 seconds h = 131.7 feet v = 47.67 feet/second t = 2.00 seconds h = 141.6 feet v = 39.62 feet/secondt = 2.25 seconds h = 149.5 feet v = 31.57 feet/second t = 2.50 seconds h = 155.4 feet v = 23.52 feet/secondt = 2.75 seconds h = 159.2 feet v = 15.47 feet/second t = 3.00 seconds h = 161.1 feet v = 7.42 feet/secondt = 3.25 seconds h = 160.9 feet v = -0.63 feet/second t = 3.50 seconds h = 158.8 feet v = -8.68 feet/secondt = 3.75 seconds h = 154.6 feet v = -16.73 feet/second t = 4.00 seconds h = 148.4 feet v = -24.78 feet/secondt = 4.25 seconds h = 140.2 feet v = -32.83 feet/second t = 4.50 seconds h = 130.0 feet v = -40.88 feet/secondt = 4.75 seconds h = 117.7 feet v = -48.93 feet/second t = 5.00 seconds h = 103.5 feet v = -56.98 feet/secondt = 5.25 seconds h = 87.2 feet v = -65.03 feet/second t = 5.50 seconds h = 69.0 feet v = -73.08 feet/secondt = 5.75 seconds h = 48.7 feet v = -81.13 feet/second t = 6.00 seconds h = 26.4 feet v = -89.18 feet/secondt = 6.25 seconds h = 2.1 feet v = -97.23 feet/second t = 6.50 seconds h = -24.2 feet v = -105.28 feet/secondEnd Script

Questions & Answers

a perfect square v²+2v+_
Dearan Reply
kkk nice
Abdirahman Reply
algebra 2 Inequalities:If equation 2 = 0 it is an open set?
Kim Reply
or infinite solutions?
Kim
y=10×
Embra Reply
if |A| not equal to 0 and order of A is n prove that adj (adj A = |A|
Nancy Reply
rolling four fair dice and getting an even number an all four dice
ramon Reply
Kristine 2*2*2=8
Bridget Reply
Differences Between Laspeyres and Paasche Indices
Emedobi Reply
No. 7x -4y is simplified from 4x + (3y + 3x) -7y
Mary Reply
is it 3×y ?
Joan Reply
J, combine like terms 7x-4y
Bridget Reply
im not good at math so would this help me
Rachael Reply
how did I we'll learn this
Noor Reply
f(x)= 2|x+5| find f(-6)
Prince Reply
f(n)= 2n + 1
Samantha Reply
Need to simplify the expresin. 3/7 (x+y)-1/7 (x-1)=
Crystal Reply
. After 3 months on a diet, Lisa had lost 12% of her original weight. She lost 21 pounds. What was Lisa's original weight?
Chris Reply
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
the Beer law works very well for dilute solutions but fails for very high concentrations. why?
bamidele Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Accessible physics concepts for blind students. OpenStax CNX. Oct 02, 2015 Download for free at https://legacy.cnx.org/content/col11294/1.36
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