Question

if a bus travelling at 20m/s is subjected to a steady retardation of 5 m/sSQUARE how long it will be take to come to rest?

Answer 1

given here
initial velocity = 20 m/s
final velocity = 0 m/s
acceleration = -5m/s^2

using formula

$v { }^{2} - u {}^{2} = 2as$
$0 {}^{2} - 20 {}^{2} = 2( - 5) \times s$
which gives s= 40 m
now using
v=u+at
0=20-5×t
which gives t= 4 seconds

kevin:)

Answer 2

hey dear
here is your answer

given data :

initial velocity (u) = 20 m/s

final velociuty (v) = 0

retardation = -5 m/s²

to find : distance travelled to come to rest (s)

solution :

by using third equation of motion

v² = u²+2as

0 = (20)²+2*(-5)*s

10s = 400

s = 40 meter

so, the bus will cover 40 meter distance

hope it helps :)