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To move an object, which one is easier, push or pull? Explain

Answer» <html><body><p></p>Solution :When a body is pushed at an arbitraryangle `theta(0 " to " (pi)/(2))`, the applied force F can be resolved into two components as F `<a href="https://interviewquestions.tuteehub.com/tag/sin-1208945" style="font-weight:bold;" target="_blank" title="Click to know more about SIN">SIN</a> theta` <a href="https://interviewquestions.tuteehub.com/tag/parallel-1146369" style="font-weight:bold;" target="_blank" title="Click to know more about PARALLEL">PARALLEL</a> to the surface and F `cos theta` perpendicularto the surface as shown in Figure. The total downward force <a href="https://interviewquestions.tuteehub.com/tag/acting-269" style="font-weight:bold;" target="_blank" title="Click to know more about ACTING">ACTING</a> on the body is `mg+Fcos theta`. It implies that the normal force acting on the body increases. Since thereis no acceleration along the verticaldirectionthe normal force N is equal to <br/> `N_("push")=mg+F cos theta""...(1)` <br/> As a result the maximal static friction also increases and is equal to <br/> `f_(s)^("max")=N_("push")=mu_(s)(mg+Fcos theta)""...(2)` <br/> Equation (2) shows that a greater force needs to be applied to push the <a href="https://interviewquestions.tuteehub.com/tag/object-11416" style="font-weight:bold;" target="_blank" title="Click to know more about OBJECT">OBJECT</a> into motion.<br/> <img src="https://d10lpgp6xz60nq.cloudfront.net/physics_images/SUR_PHY_XI_V02_G_MQP_02_E04_012_S01.png" width="80%"/> <br/> When an object is pulled at an angle `theta`, the applied force is resolved into two components as shown in Figure. The total downward force acting on the object is <br/> `N_("pull")=mg+F cos theta"" ...(3)` <br/> <img src="https://d10lpgp6xz60nq.cloudfront.net/physics_images/SUR_PHY_XI_V02_G_MQP_02_E04_012_S02.png" width="80%"/> <br/> Equation (3) shows that the normal force is less than `N_("push")`. From equations (1) and (3), it is <a href="https://interviewquestions.tuteehub.com/tag/easier-447966" style="font-weight:bold;" target="_blank" title="Click to know more about EASIER">EASIER</a> to pull an object than to push to make it move.</body></html>


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