{"id":7781,"date":"2022-08-17T06:08:15","date_gmt":"2022-08-17T06:08:15","guid":{"rendered":"https:\/\/physics.educour.in\/isc-physics\/?p=7781"},"modified":"2022-08-20T01:21:00","modified_gmt":"2022-08-20T01:21:00","slug":"laws-of-motion-class11-isc-2","status":"publish","type":"post","link":"https:\/\/physics.educour.in\/isc-physics\/laws-of-motion-class11-isc-2\/","title":{"rendered":"Laws of motion class11 ISC 2"},"content":{"rendered":"\t\t
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IMPULSE<\/strong><\/h2>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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If \u00a0a force acts on a body for a short time interval, then the product of force and its time of action, is called impulse of the force.<\/span><\/em><\/strong><\/p>

i.e. Impulse = Force \u00d7 time interval\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0<\/p>

\"\"\u00a0 \u00a0 <\/span><\/p>

\u00a0 By Newton\u2019s second law\u00a0\"\"<\/p>

\u00a0\u00a0\"\"<\/p>

\u00a0i.e\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0Impulse = Change in momentum<\/span><\/p>

Thus impulse of a force is equal to the change in momentum produced by the force.<\/span><\/em><\/strong><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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  • The SI unit of impulse is Ns.<\/li>
  • A large force acting for a short time to produce a finite change in momentum is called an impulsive force. Impulsive force is like any other force \u2013 except that it is large and acts for a short time.<\/li><\/ul>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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    Calculation of Impulse for Variable Force<\/strong><\/h3>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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    Graphical Method:<\/strong><\/span><\/h3>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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    (A) For constant Force:<\/span><\/strong><\/h4>

    In this case F versus t graph is a straight line parallel to the x \u2013 axis (time- axis)<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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    Area under the f \u2013 t graph<\/strong><\/p>

    \u00a0\u00a0= area of rectangle abcd<\/p>

    \u00a0 = ad x dc<\/p>

    \u00a0 = f .<\/strong>[t2<\/sub> \u2013 t1<\/sub>] = F. \u0394t<\/p>

    \u00a0= Impulse<\/strong> \u00a0\u00a0<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t

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    \n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\"\"\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t
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    (B) For variable force <\/span><\/strong><\/h2>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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    In this case F \u2013 t graph is a curve. Let us divide the whole area under the graph into thin strips width of each strip represent small time-interval and the average height of the strip represents the force F. So, area of each strip represents the small impulse by the force for small displacement.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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    Total area under F \u2013 t graph\u00a0<\/p>

    =\u00a0 Sum of area of all the strips<\/p>

    \u00a0= Sum of impulse for all these small time-intervals<\/p>

    \u00a0= Total Impulse.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t

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    \n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\"Graphical\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t
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    Thus, graphically, the impulse is the area between the force curve and the time axis, as shown in figure. <\/em><\/strong><\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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    Calculus Method:<\/strong><\/span><\/h3>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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    If the value of force varies with time [t] i.e. F = f(t)\u00a0 then the work done by variable force is given by<\/p>

    \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0\"\"<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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    Impulse Video<\/span><\/h2>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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    In Hindi + English Mix<\/span><\/strong><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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