tag:blogger.com,1999:blog-4366177043880918232024-03-07T22:28:43.527-08:00GCE O Level Physics NotesGCE O-Level Physics notes-an essential revision toolAvnishhttp://www.blogger.com/profile/16515626483803895432noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-436617704388091823.post-68538432046103939692009-12-17T02:29:00.000-08:002009-12-17T02:48:17.988-08:00Chapter 1-O-level Phy-Part 2 of 42.Speed<br /><br />Speed-distance travelled per unit time<br /><br />Speed= Distance/time taken ( SI units: m/s )..........EQUATION 1<br /><br />Equation 1 can ONLY be used in cases where the body is moving with constant speed.<br /><br />e.g<br />A car moves at 5 m/s for half an hour.What is the distance travelled?<br /><br />Solution: Distance= speed*time = 5*(30*60) = 9000 m<br /><br />3.AVERAGE SPEED<br /><br />Average speed = Total dist/total time taken<br /><br />Units are still m/s<br /><br />DEFINITONS:<br />SPEED: distance travelled per unit time<br />VELOCITY : rate of change of displacement<br />ACCELERATION : rate of change of velocity ( SI units: m/(s*s)<br /><br />CASE STUDY:<br /><br />Theory: A body is said to move with uniform velocity if it covers equal distances in equal time intervals while travelling along a straight line and in a specified direction.<br /><br />Problem:A car moves in a circular path at a constant speed at 10 m/s.What is its acceleration?<br /><br />Solution : Speed remains constant but the velocity changes continuously because the direction of motion is changing continuously.<br /><br />EQUATIONS OF MOTION FOR BODY MOVING WITH UNIFORM ACCELERATION:<br />v= u + at<br />s= ut + 0.5a(t*t)<br />(v*v) = (u*u) + 2as<br />s = 0.5t( u+v)<br /><br />NOTE: -ve acceleration implies that body is decelerating or undergoing retardation.<br /><br />example:<br />A car travels at 25 m/s.Driver suddenly applies brakes and car is brought to rest with uniform deceleration of 4 m/(s*s).<br />Calculate time taken for car to come to rest.<br /><br />Use v= u + at<br /><br />t = (v-u)/a = (0-25)/-4 = 6.25 s<br /><br /><br />Coming next...speed time graphs....!Avnishhttp://www.blogger.com/profile/16515626483803895432noreply@blogger.com0tag:blogger.com,1999:blog-436617704388091823.post-3074324649556349902009-12-17T01:36:00.001-08:002009-12-17T23:13:03.776-08:00Chapter 1-O-level Phy-Part 1 of 4Chapter 1-Kinematics-O-level Phy-Part 1 of 4<br />
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Scalar and Vector Quantities<br />
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Scalar quantities-Has magnitude only<br />
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Vector quantities- has magnitude & direction<br />
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1.Distance and displacement<br />
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Distance is the total length covered by a moving object without taj=king into consideration the direction in which the body is moving.<br />
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Displacement is the distance moved along a straight line in a specified direction.<br />
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example:<br />
2 boys walked from a point A to point B.<br />
Distance between the 2 points depends on the path chosen to travel between the 2 points.There may be an infinite number of paths.However,there is only 1 displacement between 2 points.It is along a straight line joining the starting and finishing points.It is the shortest possible route from A to B<br />
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NOTE: This has been a very short tutorial compared to what i plan to give all my 'fans' if this blog turns out to be popular.I shall continue with the whole syllabus if i get a good response!!!Avnishhttp://www.blogger.com/profile/16515626483803895432noreply@blogger.com2