document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=30576>Question 30576</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A circus clown at the top of a 60-foot platform is playing catch with another clown on the ground.  <BR>\n" );
document.write( "The clown on the platform drops a ball at the same time as the one on the ground tosses a ball upward at 80 ft/sec.  <BR>\n" );
document.write( "For what length of time is the distance between the balls less than or equal to 10 feet?  Hint:  the initial velocity of a ball that is dropped is 0 ft/sec.  The formula for the height S in feet above the earth at a time t seconds for an object projected into the air with an initial velocity of v ft/sec from an initial height of s0 is:<BR>\n" );
document.write( " <BR>\n" );
document.write( "S = -16t2 + v0t + s0 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #17287 by </B><A HREF=/tutors/aboutme.mpl?userid=venugopalramana><B>venugopalramana(3286)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=venugopalramana><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.geocities.com/venugopalramana/FREE_MATHS_ASSISTANCE.html valign=middle><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=17287\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> BASIS..START TIME ..0 SEC.......GROUND LEVEL =0 FT.ALL HEIGHTS MEASURED FROM GROUND LEVEL.<BR>\n" );
document.write( "WE HAVE 2 BODIES B1 COMING DOWN FROM TOP TO GROUND...SAY.... U TO P.<BR>\n" );
document.write( "B2 GOING UP FROM GROUND UPWARDS......SAY....P TO U....(OFCOURSE NOT CLASHING)<BR>\n" );
document.write( "ATTACHMENTT:-<BR>\n" );
document.write( "LET B1 COME DOWN FROM U TO R AND B2 GO UP FROM P TO Q WHEN THEY ARE AT THE 10 FEET SEPERATION ASKED FOR.THIS IS THE ATTACHMENT LET US SAY.LET THIS HAPPEN IN T1 SECS.FROM START.WE HAVE<BR>\n" );
document.write( "PU=60 FEET...LET PQ=X FT.....QR=10 FT.....HENCE PR=X+10 FEET.<BR>\n" );
document.write( "DISTANCE TRAVELLED IN T SECS.FROM START,MEASURED FROM GROUND LEVEL IS GIVEN BY<BR>\n" );
document.write( "S=-16T^2+(V0)T+(S0).....WHERE V0 IS INITIAL VELOCITY AND S0 IS START DISTANCE FROM GROUND.<BR>\n" );
document.write( "SO FOR B1 COMING DOWN WE HAVE   <BR>\n" );
document.write( "X+10=-16T1^2+0*T1+60=-16T1^2+60...............................I<BR>\n" );
document.write( "FOR B2 GOING UP ,WE HAVE...<BR>\n" );
document.write( "X=-16T1^2+80T1+0=-16T1^2+80T1..................................II<BR>\n" );
document.write( "SUBSTITUTING FOR X FROM EQN.II IN EQN.I,WE GET<BR>\n" );
document.write( "-16T1^2+80T1+10=-16T1^2+60<BR>\n" );
document.write( "80T1=50<BR>\n" );
document.write( "T1=50/80=5/8 SECS.<BR>\n" );
document.write( "SO THE ATTACHMENT TAKES PLACE T 5/8 SEC. FROM START.<BR>\n" );
document.write( "DETACHMENT:-<BR>\n" );
document.write( "NOW B1 CONTINUES TO COME DOWN AS B2 GOES UP,CROSSING EACH OTHER,WHEN THE DISTANE BETWEEN THEM COMES DOWN FROM 10 FT. TO ZERO.AS THEY FURTHER CONTINUE THEIR TRAVEL ,THEIR DISTANCE OF SEPERATION INCREASES FROM ZERO TO 10 FT.LET US CALL THIS DETACHMENT.LET THIS HAPPEN AFTER T2 SECS.FROM START WHEN B1 REACHES SAY S AND B2 REACHES T.WE HAVE..<BR>\n" );
document.write( "LET PT=Y AND HENCE PS=Y-10...SO FOR THIS PART<BR>\n" );
document.write( "FOR B1 COMING DOWN WE HAVE..<BR>\n" );
document.write( "Y-10=-16T2^2+0*T2+60=-16T2^2+60...........................III<BR>\n" );
document.write( "FOR B2 GOING UP,WE HAVE..<BR>\n" );
document.write( "Y=-16T2^2+80T2+0=-16T2^2+80T2...........................IV<BR>\n" );
document.write( "SUBSTITUTING FOR Y FROM EQN.III IN EQN.IV..WE GET<BR>\n" );
document.write( "-16T2^2+80T2-10=-16T2^2+60<BR>\n" );
document.write( "80T2=70<BR>\n" );
document.write( "T2=7/8 SECS.<BR>\n" );
document.write( "SO THE DETACHMENT TAKES PLACE AT 7/8 SECS.FROM START.<BR>\n" );
document.write( "SO FOR 7/8-5/8=2/8=1/4 SECS.THE 2 BALLS ARE AT A DISTANCE OF 10 FEET OR LESS.    </SPAN>\n" );
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