document.write( "Question 1162369: Suppose you wanted to model a ferris wheel using a sine function that took 60
\n" ); document.write( "seconds to complete one revolution. The ferris wheel must start 0.5 m above ground.\r
\n" ); document.write( "\n" ); document.write( "Provide an equation of such a sine function that will ensure that the ferris wheel’s minimum height of the ground is 0.5 m.
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Algebra.Com's Answer #786156 by Theo(13342)\"\" \"About 
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the general form of the sine function is y = a * sin(b * (x - c)) + d
\n" ); document.write( "a is the amplitube
\n" ); document.write( "b is the frequency
\n" ); document.write( "c is the horizontal shift
\n" ); document.write( "d is the vertical shift.
\n" ); document.write( "formula for frequency is f = 360 / p
\n" ); document.write( "f is the frequency
\n" ); document.write( "p is the period
\n" ); document.write( "if you want one full sine wave to be 60 seconds, then let 60 degrees represent 60 seconds.
\n" ); document.write( "your period is 60 seconds.
\n" ); document.write( "f = 360 / 60 = 6
\n" ); document.write( "if your frequency is 6, then you will get 6 full sine waves in 360 degrees.
\n" ); document.write( "that would make each full sine wave equal to 60 degrees.
\n" ); document.write( "with b = 6, your sine wave function becomes y = a * sin(6 * (x - c)) + d
\n" ); document.write( "when a = 1, the sine wave is plus or minus 1 unit from the center line of the sine wave.
\n" ); document.write( "that makes the top 1 unit above the center line and the bottom 1 unit below the center line.
\n" ); document.write( "the center line of the sine wave is the x-axis without any adjustment.
\n" ); document.write( "if you let the x-axis represent the ground and you want the bottom of the sine wave to be .5 units above the ground, then d must be equal to 1.5
\n" ); document.write( "that raises the center line of the sine wave to y = 1.5 which means the bottom of the sine wave will be at y = .5 which is .5 units above the ground.
\n" ); document.write( "set d to 1.5 and the formula becomes y = a * sin(6 * (x - c)) + 1.5
\n" ); document.write( "let's take a look at whaat we have so far.
\n" ); document.write( "since c is normally 0, we set it to 0.
\n" ); document.write( "since a is normall 1, we set it to 1.
\n" ); document.write( "the function becomes y = 1 * sin(6 * (x - 0)) + 1.5
\n" ); document.write( "this is what it looks like on the graph.\r
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\n" ); document.write( "\n" ); document.write( "the sine wave starts at the center line which is 1.5 units above the x-axis which represents the ground.
\n" ); document.write( "we want the sine wave to start at .5 units above the ground.
\n" ); document.write( "from the graph we can see that if we shift the sine wave to the right 15 degrees, then it will start .5 units above the ground.
\n" ); document.write( "we need a horizontal shift to the right of 15 degrees.
\n" ); document.write( "shift to the right means c must be positive.
\n" ); document.write( "therefore we make c = 15 and the formula becomes y = 1 * sin(6 * (x - 15)) + 1.5
\n" ); document.write( "this is what that looks like on the graph.\r
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\n" ); document.write( "\n" ); document.write( "the final diagram is what you want.
\n" ); document.write( "one full cycle is 60 degrees which represents 60 seconds.
\n" ); document.write( "the cycle starts .5 meters above the ground.
\n" ); document.write( "the a point on the ferris wheel has a minimum height of .5 meters above the ground and a maximum height of 2.5 meters above the ground.
\n" ); document.write( "the amplitude of the sine plus or minus 1 unit from the center line which is at 1.5 meters above the ground.
\n" ); document.write( "the point on the ferris wheel that was .5 meters from the ground when it starts will be back to .5 meters above the ground every 60 seconds.\r
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\n" ); document.write( "\n" ); document.write( "here's a view of what the sine wave looks like after it went through three 60 second cycles.\r
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\n" ); document.write( "\n" ); document.write( "your final equation was y = 1 * sin(6 * (x-15)) + 1.5\r
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\n" ); document.write( "\n" ); document.write( "since a = 1 is default, the equation can be written as y = sin(6 * (x-15)) + 1.5\r
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\n" ); document.write( "\n" ); document.write( "here's a reference on the equation to graph a sine wave.\r
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\n" ); document.write( "\n" ); document.write( "https://mathbitsnotebook.com/Algebra2/TrigGraphs/TGsinusoidal.html
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