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Kinematic and Motion. KJS 2233 Mechanic of Machine. Type of Motions. Linear Angular. Linear Motion. Equations. Example. a)Determine the acceleration of a sport car if time taken to hit 100 km/h is 5 second. b)Determine the distance from starting point to achieve 100 km/h. answer.
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Kinematic and Motion KJS 2233 Mechanic of Machine
Type of Motions • Linear • Angular
Linear Motion • Equations
Example a)Determine the acceleration of a sport car if time taken to hit 100 km/h is 5 second. b)Determine the distance from starting point to achieve 100 km/h
answer a) 5.5 m/s2 b) 69.75m
Example • An object fall from a building, determine its velocity after 1s and 2s.
answer • 9.81 m/s • 19.62 m/s
Angular Motion Equations
Example A gear rotates counter clock wise at constant speed. It moves 300O in 0.5 s. Determine its angular velocity.
Answer = 600 deg/s or 50 rpm
Example The mechanism below show the component used in exhaust port of internal combustion engine. Cam forces rocker arm at point B with velocity of 30mm/s. Determine angular velocity of angular plate and velocity at point C.
Answer W2= vb/rb =30/20 = 1.5 rad/s • Vc= rw • =15 mm x 1.5 rad/s • =22.5 mm/s
Example An electric motor will speed up to 1800 rpm in 2 s when the power is turned on. Assuming the speed up is at constant rate. Determine the angular acceleration of motor. Also determine the number of revolutions that the wheel spins before it is at full speed.
answer 188.6 rad or 30 revolutions
Answer Rev= 82 rev
Example A flywheel with diameter of 200 mm accelerates from 2000 rpm to 6000 rpm within 10 s. Determine its tangent and normal acceleration.
Answer • Answer; • 2000 rpm= 209.44 rad/s • 6000 rpm= 628.32 rad/s • 𝜶=41.892 • at = (41.892)x( 0.1)=4.1 • At 2000 rpm • an= (209.44)2x(0.2) • = 8773.02 m/s2 • At 6000 rpm • an= (628.32)2x(0.2) • = 78957.2 m/s2