A bus decreases it's speed from 80kmper hourto 60kmperhour in 5sec .Find the acceleration of the bus
Answers
Assuming a straight-path condition.
Answer:
- 1.1 m / s^2.
Explanation:
Here,
Initial velocity of the bus is :
80 km per hour = 80 x 1000 / 3600 m / s or 80 x 5 / 18 m / s
Initial velocity is ( 200 / 9 ) m / s
Final velocity of the bus is :
60 km pr hour = 60 x 5 / 18 m / s = ( 150 / 9 ) m / s
We know, acceleration defines the change in velocity wrt time.
⇒ Acceleration = ( 150 / 9 - 200 / 9 ) / ( time taken )
⇒ ( 150 / 9 - 200 / 9 ) / 5
⇒ ( - 50 / 9 ) / 5
⇒ - 50 / ( 9 x 5 )
⇒ - 50 / 45
⇒ - 10 / 9
⇒ - 1.1 m / s^2
Explanation:
Given -
u = 80 Km/h (initial velocity)
v = 60 Km/h (final velocity)
t = 5 seconds (time)
To Find -
acceleration = ?
Now,
As we know that,
- v = u + at
here,
v = final velocity
u = initial velocity
a = acceleration
t = time
u = 80 Km/h
= 80 × 1000/60 × 60
- = 22.22 m/s
and
v = 60 Km/h
= 60 × 1000/60 × 60
- = 16.66 m/s
Now,
- acceleration = v - u/t
= a = 16.66 - 22.22/5
= a = -5.56/5
= a = - 1.112 m/s²
Hence,
The acceleration of the bus is
-1.112 m/s²
Formula Used -
- v = u + at
Some related formulas -
- s = ut + 1/2at²
- v² = u² + 2as
here,
v = final velocity
u = initial velocity
a = acceleration
t = time
s = distance