A train starts from rest and after 20 seconds is traveling at 30 MS⁻¹. It travels at this speed for one minute. How do I find the acceleration in the first 20s and the total distance traveled?
Answers
Explanation:
data:
vi=0m/s
t=20sec
vf=30m/s
a=?
s=?
solution:
first find acceleration with the help of first equation of motion
vf=vi+at
30=0+a(20)
30/20=a
a=1.5m/s²
now find" s "with the help of 3 equation of motion
2as=vf²-vi²
2(1.5)s=30²-0²
3s=900-0
s=900/3
s=300m
Answer:
The acceleration of the train is 1.5 m/s².
The total distance traveled by the train is 300 m.
Explanation:
The train starts from rest. So its initial velocity, u = 0 m/s
Final velocity of the train, v = 30 m/s
Time taken to attain this velocity, t = 20 s
Acceleration of the train in 1st 20 seconds can be found from the 1st equation of motion.
v = u + at
a = (v - u) / t
a = (30 - 0) / 20
a = 1.5 m/s²
The total distance traveled by train is found using the 3rd equation of motion.
v² - u² = 2aS
S = (v² - u²) / 2a
S = (30² - 0²) / (2 × 1.5)
S = 900 / 3
S = 300 m