document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1079694>Question 1079694</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose the pendulum string is attached to a point on the ceiling 30 cm from the wall. The weight is moved away from its rest position and released at time t=0. At time t=1.4 sec, it reaches its maximum distance from the wall, 37.4 cm away, and then swings back toward the wall again. At times 2.8 sec, the weight reaches a minimum distance of 23.2 cm form the wall, and then swings away again.<BR>\n" );
document.write( "a. assuming that the amplitude of the pendulum's swing decreases exponentially with the time, find an equation expressing the amplitude A in terms of time t.<BR>\n" );
document.write( "b. find an equation modeling the weight's distance from the wall<BR>\n" );
document.write( "c. at the moment the weight was released, what angle did the string make with  the ceiling<BR>\n" );
document.write( "Can someone help me with this?<BR>\n" );
document.write( "Thanks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #695049 by </B><A HREF=/tutors/aboutme.mpl?userid=KMST><B>KMST(5328)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=KMST><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=KMST><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=695049\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> HINTS:<BR>\n" );
document.write( "In physics, the period of a pendulum is supposed to be a constant,<BR>\n" );
document.write( "depending on the length of the string, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=L ALIGN=MIDDLE  ALT=\"L\"   DISABLED_style= \"max-width:90%; height:auto;\" > ,<BR>\n" );
document.write( "and the acceleration of gravity, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=g=about ALIGN=MIDDLE  ALT=\"g=about\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9.8 ALIGN=MIDDLE  ALT=\"9.8\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m%2Fs%5E2 ALIGN=MIDDLE  ALT=\"m%2Fs%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > :<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=T=2pi%2Asqrt%28L%2Fg%29 ALIGN=MIDDLE  ALT=\"T=2pi%2Asqrt%28L%2Fg%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > .<BR>\n" );
document.write( "The period is the time between two consecutive times the pendulum is closest to the wall.<BR>\n" );
document.write( " <BR>\n" );
document.write( "If you know the pendulum started at <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%5B0%5D ALIGN=MIDDLE  ALT=\"A%5B0%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" > away from the vertically down equilibrium position,<BR>\n" );
document.write( "swinging in an arc of radius <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=L ALIGN=MIDDLE  ALT=\"L\"   DISABLED_style= \"max-width:90%; height:auto;\" > ,<BR>\n" );
document.write( "you can calculate the initial angle between string and the vertical.<BR>\n" );
document.write( " <BR>\n" );
document.write( "Assuming the ceiling is horizontal, you can relate that to<BR>\n" );
document.write( "the initial angle between the string and the ceiling.<BR>\n" );
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