{"id":3147,"date":"2023-10-04T12:07:47","date_gmt":"2023-10-04T12:07:47","guid":{"rendered":"http:\/\/localhost\/ecole9ja\/?p=3147"},"modified":"2023-10-04T12:23:00","modified_gmt":"2023-10-04T12:23:00","slug":"week-11-ss2-second-term-further-mathematics-notes","status":"publish","type":"post","link":"https:\/\/ecolebooks.com\/nigeria\/posts\/week-11-ss2-second-term-further-mathematics-notes\/","title":{"rendered":"Week 11 &#8211; SS2 Second Term Further Mathematics Notes"},"content":{"rendered":"<p>\u00a0<strong>WEEK ELEVEN<br \/>\n<\/strong><strong>TOPIC:WORK, POWER AND ENERGY ;IMPULSE AND MOMENTUM<br \/>\n<\/strong><strong>Work<br \/>\n<\/strong>If the point of application of a force is displaced, the force is said to do work. For a constant force <em>F<\/em>, whose point of application is given a displacement <em>d<\/em>, work done is the product of <em>\/F<\/em>\/ and <em>d<\/em>.<br \/>\nThe <strong>work<\/strong> done by a constant force is defined as the product of the force and the distance moved by its point of application along the line of application of the force.<br \/>\n<em>W<\/em>= \/ <em>f<\/em>\/<em>d<br \/>\n<\/em><br \/>\n\u00a0Consider a force<em> F <\/em>displaced a distance d along is line of application<em> AB.<img decoding=\"async\" align=\"left\" src=\"https:\/\/ecolebooks.com\/nigeria\/wp-content\/uploads\/9jalessonsimages\/100423_1207_Week11SS2S1.png\" alt=\"\"\/><br \/>\n\t\t\t<\/em><img decoding=\"async\" align=\"left\" src=\"https:\/\/ecolebooks.com\/nigeria\/wp-content\/uploads\/9jalessonsimages\/100423_1207_Week11SS2S2.png\" alt=\"\"\/><img decoding=\"async\" align=\"left\" src=\"https:\/\/ecolebooks.com\/nigeria\/wp-content\/uploads\/9jalessonsimages\/100423_1207_Week11SS2S3.png\" alt=\"\"\/><img decoding=\"async\" align=\"left\" src=\"https:\/\/ecolebooks.com\/nigeria\/wp-content\/uploads\/9jalessonsimages\/100423_1207_Week11SS2S4.png\" alt=\"\"\/><\/p>\n<p>\u00a0<br \/>\n\u00a0If the magnitude of the displacement is d then<br \/>\n<em>W<\/em>= \/<em>F<\/em>\/ <img decoding=\"async\" src=\"https:\/\/ecolebooks.com\/nigeria\/wp-content\/uploads\/9jalessonsimages\/100423_1207_Week11SS2S5.png\" alt=\"\"\/> d<br \/>\n<strong>Power<br \/>\n<\/strong>Power is the rate at which work is being done. For example, if work of 90j is done in 15 seconds, the power is 6J\/sec. The unit of power is the<strong> Watt<\/strong> (W)<br \/>\nExample 16<br \/>\nOn the level, a car develops a power of 60KW. if the resistance to motion is 9ooN, what is the maximum speed of the car?<br \/>\nWorking at the same power and with the same resistance operating, what would be the maximum speed possible up an inclined plane whose slope is sin<sup>-1<\/sup>, if the mass of the car is 800kg?<br \/>\nWhat is the acceleration at the time when the car is moving up the inclined plane at 40ms<sup>-1<\/sup>? (Take g= 10ms<sup>-2<\/sup>)\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0<strong><br \/>\n\t\t\t<\/strong><strong>Solution<br \/>\n<\/strong>Let<em> P<\/em> be the power developed by the car.<br \/>\nLet <em>W<\/em> be the work done.<br \/>\nLet <em>F<\/em> be the tractive force of the car<br \/>\nP =  (w)<br \/>\n= (f)<\/p>\n<p>\u00a0<strong>Energy<br \/>\n<\/strong><strong>Kinetic Energy<br \/>\n<\/strong>The work done in bringing a particle of mass m from rest to a velocity v is called the kinetic energy of the particle<br \/>\nIf we donate E<sub>k<\/sub> as the kinetic of particle of mass m reaching a velocity v from rest, then<br \/>\nE<sub>k<\/sub> =<em>mv<\/em><sup>2<br \/>\n<\/sup>If <em>W<\/em> is the work done in bringing the particle of mass <em>m<\/em> to a velocity v from an initial velocity <em>u<\/em>, and if <em>s<\/em> is the distance travelled in the process, then<br \/>\n<em>W= F<br \/>\n<\/em><em>=m <\/em>where <em>a<\/em> is the acceleration<br \/>\nBut<br \/>\n<em>s =<br \/>\n<\/em><em>a=<br \/>\n<\/em><em>:. W = m<br \/>\n<\/em><img decoding=\"async\" align=\"left\" src=\"https:\/\/ecolebooks.com\/nigeria\/wp-content\/uploads\/9jalessonsimages\/100423_1207_Week11SS2S6.png\" alt=\"\"\/><img decoding=\"async\" align=\"left\" src=\"https:\/\/ecolebooks.com\/nigeria\/wp-content\/uploads\/9jalessonsimages\/100423_1207_Week11SS2S7.png\" alt=\"\"\/><em>= m<br \/>\n<\/em>=<em>mv<\/em><sup>2<\/sup> &#8211;<em>mu<sup>2<\/sup><\/em><br \/>\n\t\tIf we denote the last expression b<img decoding=\"async\" src=\"https:\/\/ecolebooks.com\/nigeria\/wp-content\/uploads\/9jalessonsimages\/100423_1207_Week11SS2S8.png\" alt=\"\"\/><br \/>\n\t\t<img decoding=\"async\" src=\"https:\/\/ecolebooks.com\/nigeria\/wp-content\/uploads\/9jalessonsimages\/100423_1207_Week11SS2S9.png\" alt=\"\"\/>E<sub>k<\/sub> = mv<sup>2<\/sup> &#8211;  mu<sup>2<br \/>\n<\/sup><img decoding=\"async\" src=\"https:\/\/ecolebooks.com\/nigeria\/wp-content\/uploads\/9jalessonsimages\/100423_1207_Week11SS2S10.png\" alt=\"\"\/>E<sub>k<\/sub>is the change in kinetic energy in bringing a particle of mass <em>m<\/em> from an initial velocity<em> u<\/em> to final velocity <em>v<\/em><\/p>\n<p>\u00a0<strong>Potential energy<br \/>\n<\/strong>Potential energy of a particle of mass <em>m<\/em> is the energy of the particle, by virtue of its position relative to a reference level. It is the work done in bringing a particle from a reference level to a height<em> h<\/em><br \/>\n\t\tIf we donate the potential energy by E<sub>k<\/sub> then<br \/>\nE<sub>p<\/sub> =<br \/>\nSince F = <em>mg<\/em>, and S = <em>\/<\/em><br \/>\n\t\tE<sub>p<\/sub>= mgh<\/p>\n<p>\u00a0<strong>Law of Conversation of Energy<br \/>\n<\/strong>This is a generalization if the experience from nature and it state that energy cannot be created nor destroyed. It can only be changed from one from to another<br \/>\nWhen a particle falls from a height, it loses potential energy. This loss in potential energy is compensated for, in the gain in kinetic energy<br \/>\n<strong>Example<br \/>\n<\/strong>A particle starting from rest falls freely from a height <em>H<\/em> above the ground. If <em>g<\/em> is the acceleration due to gravity, show from energy consideration that the velocity <em>v<\/em> with which the particle strikes the ground is given by the expression<br \/>\n<em>v<\/em> =<br \/>\n<strong>Solution<br \/>\n<\/strong>Let the particle have mass <em>mkg.<\/em><br \/>\n\t\tLoss of potential energy = <em>mgH<\/em>.<br \/>\nGain in kinetic energy = <sup> 2<\/sup><br \/>\n\t\tfrom the principle of conversation of energy:<br \/>\nImpulse and Momentum<br \/>\nWe recall from Newton&#8217;s secondary law of motion that for a constant force <em>F<br \/>\n<\/em><em>F = m<br \/>\n<\/em><em>or F dt = m dv<br \/>\n<\/em>The expression on the L.H.S. of (1) gives the time- effect of force and is called Impuse. The expression on the R.H.S gives the velocity effect of mass and is called change in momentum. The expression (1) is a restatement of newton&#8217;s second law of motion ant it states that <strong>the time- effect of force is equal to the change in momentum<\/strong>.<br \/>\nFrom Newton&#8217;s second law of motion<br \/>\n<em>F = m <\/em>=<em> ma<\/em><\/p>\n<p>\u00a0<strong>GENERAL EVALUATION<br \/>\n<\/strong>1) A body of mass 20kg moves a distance of 8m in the direction of line of action of force F =5N  on a smooth table find the work done<br \/>\n2) A particle of mass 3kg is projected vertically upward with an initial velocity of 5 m\/s from the ground, calculate the potential energy at the greatest height<br \/>\n3) A sphere of mass 12kg and another sphere of 8kg moves toward each other with velocities 5 m\/s and 3 m\/s respectively find the speed of the sphere after collision<br \/>\n4) Calculate the loss in kinetic energy caused by the collision of the two bodies above in (3)<\/p>\n<p>\u00a0<strong>Reading Assignment<\/strong><br \/>\n\t\tNew Further Maths Project 2 page 245 \u2013 257<\/p>\n<p>\u00a0<strong>WEEKEND ASSIGNMENT<br \/>\n<\/strong>A body at rest and of mass 8kg is acted upon by a force of 30N for 0.4 seconds, calculate the<br \/>\n1) impulse on the body  a) 120Ns   b) 240Ns  c) 3.2Ns  d) 12Ns<br \/>\n2) final speed of the body  a) 1.5m\/s  b) 2.5m\/s  c) 2.0m\/s  d) 3m\/s<br \/>\n3) distance covered within the time interval a) 3m  b) 30m  c) 0.3m  d) 0.354m<br \/>\n4) kinetic energy possessed by the body a) 6J  b) 9J  c) 12J  d) 15J\u00a0\u00a0\u00a0\u00a0<br \/>\n5) power of the body  a) 50W  b) 22.5W  c) 45W  d) 12.5W<\/p>\n<p>\u00a0<strong>THEORY\u00a0\u00a0\u00a0\u00a0<br \/>\n<\/strong>1) A body of mass 6kg moves with speed 3m\/s , if it is acted upon by a force of 18N for 4 seconds find the speed of the body.<br \/>\n2) The resistance to the motion of a cart being pushed by a man is 220N, if the man pushed the cart a distance of 10km  for 45 mins calculate (i) the work done by the man  (ii) power exerted by the man.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u00a0WEEK ELEVEN TOPIC:WORK, POWER AND ENERGY ;IMPULSE AND MOMENTUM Work If the point of application&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1,253],"tags":[],"class_list":["post-3147","post","type-post","status-publish","format-standard","hentry","category-posts","category-second-term-ss2-further-mathematics"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/posts\/3147","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/comments?post=3147"}],"version-history":[{"count":1,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/posts\/3147\/revisions"}],"predecessor-version":[{"id":3148,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/posts\/3147\/revisions\/3148"}],"wp:attachment":[{"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/media?parent=3147"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/categories?post=3147"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/tags?post=3147"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}