a train starts from restwith an acceleration of 0.5ms .find its speed in kmh , when it has moved through 100m
Answers
Explanation:
Given Data
Velocity = v = 36kmh-1
v = 36 × 1000/3600
v = 10ms-1
Time = t = 10 s
To find
Distance = s = ?
Formula
velocity = distance/time
v = S/t
S = v × t
Calculation
As
S = v × t
By putting the values
S = 10 × 10 = 100 m
S = 100m
Hence total distance will be 100m
2. A train starts from rest. It movies through 1 km in 100 s with uniform acceleration. What will be its speed at the end of 100 s.
Given Data
Initial velocity = vi = 0 ms-1
Distance = S = 1km = 1000m
Time = t =100 s
To find
Final Velocity = vf =?
Formula
S = vit+1/2 at2
vf = vi + at
Calculation
First of all we have to find “a” after getting the value of “a” we have to find “vf”.
S = vit+1/2 at2
By putting the values we get,
1000 = (0) × 100 + 1/2 × (a) × (100)2
Opening the square of 100.
1000 = 1/2 × (a) × (10000)
By dividing 2.
1000 = (a) × (5000)
By Dividing 5000 both sides
1000/5000 = a
a = 0.2 ms-2
Now we have to calculate the value of “Final Velocity” like as,
vf = vi + at
Putting the values we, get
vf = 0 + (0.2)×100
Multiplying 0.2 by 100
vf = 20 ms-1
Hence the body having the final velocity of
vf = 20 ms-1