a bus started from Kathmandu and reached khanikhola 26 km far from Kathmandu , in one hour. if the bus had uniform acceleration, calculate the final velocity of the bus and acceleration.
Answers
Explanation:
The initial velocity u of the bus when it started from rest = 0 m/s
The distance s travelled by the bus in 1 hour ( t =3600 s) = 26 km = 26,000 m
Let the final velocity of the bus = v m/s
Using the relation
s = u t + ½ a t²
Substituting the values for s = 26,000 m; u = 0 m/s; t = 3600 s, we get
26,000 = 0 × 3600 + ½ a × 3600²
=> 26,000 × 2 = a × 3600²
=> a = 52, 000/3600 × 3600 = 13/3240 m/s²
Final velocity = v m/s
v = u + a t = 0 + (13/3240) × 3600 = 130/9 m/s = (130/9) × 3600 = 52,000 m/h = 52 km/h.
A much shorter method would be to use the concept of average velocity.
The distance covered = average velocity × time of travel;
½ (initial velocity + final velocity) × one hour = 26 km
=> (initial velocity + final velocity) = 52 km/h
=> (0 + final velocity) = 52 km/h
=> Final velocity = 52 km/h.