Answer:
It will take 10 hours.
Step-by-step explanation:
By using the formula of motion,
v = u + at
Here, v = Final speed of an object
u = initial speed
a = Acceleration by which the speed is increasing
t = Duration or time
Now substitute the values given in the question,
80 = 50 + 3t
3t = 30
t = 10 hours
Therefore, after 10 hours speed of the bus will be 80 mph.
