Question

plz ans this..............

Answer 1

Hello!! friend
Here is ur answer...

Actually, the object is undergoing retardation..
80km/hr= 200/9 m/sec
60 km/hr=50/3 m/sec
time =5 sec
retardation = 200/9-50/3. /5
50/9*5 =250/9 m/sec

Answer 2

80 kmph = 80 × 5/18 m/s = 22.2 m/s
60 kmph = 60 × 5/18 m/s = 16.7 m/s

Acceleration (a): Rate of change of velocity

a = (v - u) / t
= (16.7 m/s - 22.2 m/s) / (5 s)
= -1.1 m/s

Acceleration is negative because it’s in the direction opposite to that of direction of velocity.