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Laws Of Motion

Question
CBSEENPH11017025

A car is taking turn on the rough banked circular track. What should be the velocity of car so that there is no wear and tear of the tyres?

Solution

Consider a car of mass m taking the turn on banked rough circular track of radius r.
Let straight theta be the angle of banking and μ be the coefficient of friction.
Let u be the velocity of car so that there is no wear and tear.
Different forces acting on car are:
(i) Weight of car, acting vertically downwards.
(ii) Reaction R on car, normal to track.
(iii) Frictional force f = μR, down the inclined plane.
(iv) Centrifugal force <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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Resolving the rectangular component of different forces.
Since there is no wear and tear on the car, therefore, net force in vertical and horizontal direction is zero. 
That is, 
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