Question

A car is moving on straight highway with a speed of 108 km/h.

Answer 1

5.3333 sec

Step-by-step explanation:

initial speed: u = 108km/hr or 30 m/s

final speed: v = 0m/s

distance travelled: s = 80m

time the car took to stop: = t sec

`v^(2) - u^(2)` = 2as,

a = (
`v^(2) - u^(2)`)/2s

a = (0-900)/160

a = -5.625
`ms^(-2)`

v = u + at,

t = (v - u)/a

t= (0 - 30)/(-5.625)

t = 5.3333 sec