<text><span class="style10">otion and Force (3 of 5)Circular motion</span><span class="style7">If a body moves in a circular path at constant speed its direction of motion (and therefore its velocity) will be changing continuously. Since the velocity is changing, the body must have acceleration, which is also changing continuously. Thus the laws of uniformly accelerated motion do not apply. The acceleration of a body moving in a circular path is called the </span><span class="style26">centripetal</span><span class="style7"> (`center-seeking') </span><span class="style26">acceleration</span><span class="style7">. This is directed inward, towards the center of the circle. </span></text>
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<text><span class="style10">. Centripetal acceleration.</span><span class="style7"> At point P the body is moving with instantaneous velocity </span><span class="style26">v</span><span class="style7">. The centripetal acceleration along PO is </span><span class="style26">v2/r2</span><span class="style7"> (where </span><span class="style26">r</span><span class="style7"> is the radius of the circle), and this force prevents the body from moving in a straight line along PV.</span></text>
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<text>ΓÇó THE HISTORY OF ASTRONOMYΓÇó FORCES AFFECTING SOLIDS AND FLUIDSΓÇó THERMODYNAMICSΓÇó QUANTUM THEORY AND RELATIVITYΓÇó THE HISTORY OF SCIENCEΓÇó FUNCTIONS, GRAPHS AND CHANGE</text>