Question
A stone tied to the end of a string 80 cm long is whirled in a horizontal circle with constant speed. If the stone makes 14 revolutions in 25 seconds then what is the magnitude and direction of acceleration of the stone?
Solution
Given,
Length of the string, l = 80cm
No. of revolutions made by the stone in 25 seconds = 14
angular speed, ![<pre>uncaught exception: <b>mkdir(): Permission denied (errno: 2) in /home/config_admin/public/felixventures.in/public/application/css/plugins/tiny_mce_wiris/integration/lib/com/wiris/util/sys/Store.class.php at line #56mkdir(): Permission denied</b><br /><br />in file: /home/config_admin/public/felixventures.in/public/application/css/plugins/tiny_mce_wiris/integration/lib/com/wiris/util/sys/Store.class.php line 56<br />#0 [internal function]: _hx_error_handler(2, 'mkdir(): Permis...', '/home/config_ad...', 56, Array)
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Therefore acceleration of stone is,
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Here, motion of stone is circular motion. Therefore, acceleration of stone at any instant is directed towards the centre along the radius.
