أستاذ , علي .. لدي 4 مسائل جديدة تخص الحركة في خط أفقي , حتى الآن لم اقم بحل ايا منها لانشغالي بدراسة مواد أخرى , فاتمنى منك حلها :
1 - spotting a police car , you brake a porsche from 75 km/h to 45 km/h over a displacement of 88 m .
A - what's the acceleration , assumed to be constant ?
B - what's the elapsed time ?
C - if you continue to slow down with the acceleration calculated in ( a ) , how much time will elapse in bringing the car to rest from 75 km/h ?
D - in ( c ) , what's distance will be covered ?
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2 - an automobile travels with constant acceleration is brought to stop from a speed of 20 m / s in a distance of 40 m .
A - what's acceleration ?
B - what's the time it takes to stop the car ?
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3 - a race car is moving at a constant speed of 35 m / s , passes stationary police car . The police car starts moving with a constant acceleration of 4 m/s^2 . Find the distance at which the police car overtakes the race car ?
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4 - a motorcyclist heading east through a small town accelerates as he passes the signpost at x=0 m marking the city limits . His acceleration is constant a = 4 m/sec^2 . At time t = 0 he's at x=5 m and his velocity v=3 m/sec
a - find his position and velocity at time t=2 sec
b - where's he when his velocity is 5 m/sec ?
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شكرا مقدما , وراح اخبرك بمطابقة حلي لحلك لاحقا عندما اتفرغ لها .