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A car is moving with a speed of 22 m/s. The driver then brakes, and the car comes to a halt after 6.5 s. What is the distance covered by the car after the driver brakes, until it comes to a stop?

Respuesta :

badddiee
acceleration --- (-a) 
velocity = -at + c 
when t = 0, v = 22 
22= 0+c ---> c = 0 
v = -at + 22 
when t = 6.5, v = 0 
0 = -6.5a + 22 
a = 22/6.5 = 44/13 


distance = d = (-1/2)a t^2 + 22t + k 
d = (-22/13)t^2 + 22t + k 
when t = 0, d = 0, so k = 0 
velocity = -at + c 
when t = 0, v = 22 
22= 0+c ---> c = 0 
v = -at + 22 
when t = 6.5, v = 0 
0 = -6.5a + 22 
a = 22/6.5 = 44/13 


distance = d = (-1/2)a t^2 + 22t + k 
d = (-22/13)t^2 + 22t + k 
when t = 0, d = 0, so k = 0