Question

8. From the station 'X a train starts from rest and attains a speed of 54km/h in 10 seconds. Calculate the acceleration of the train.​

Answer 1

Answer:

1.5 m/s2

Explanation:

   Velocity(v)= 54km/hr = 54 x 5/18  m/s  =15 m/s

   Acceleration(a)= v/t = 15/10 = 1.5 m/s2

Answer 2

Provided that:

• Initial velocity = 0 mps
• Final velocity = 54 kmph
• Time = 10 seconds

To calculate:

• The acceleration

Solution:

• The acceleration = 1.5 mps sq.

Using concepts:

• Acceleration formula
• Formula to convert kmph-mps

Using formulas:

• Acceleration is given by,

• ${\small{\underline{\boxed{\sf{a \: = \dfrac{v-u}{t}}}}}}$

Where, a denotes acceleration, v denotes final velocity, u denotes initial velocity, t denotes time taken.

• Formula to convert kmph-mps:

• ${\small{\underline{\boxed{\sf{1 \: kmph \: = \dfrac{5}{18} \: mps}}}}}$

Required solution:

~ Firstly let us convert kilometre per hour into metre per second!

$\begin{gathered}:\implies \sf 54 \times \dfrac{5}{18} \\ \\ :\implies \sf \cancel{54} \times \dfrac{5}{\cancel{{18}}} \\ \\ :\implies \sf 3 \times 5 \\ \\ :\implies \sf 15 \: ms^{-1} \\ \\ {\pmb{\sf{Henceforth, \: converted!}}}\end{gathered}$

~ Now by using acceleration formula let us find out the acceleration!

$:\implies \sf a \: = \dfrac{v-u}{t} \\ \\ :\implies \sf a \: = \dfrac{15-0}{10} \\ \\ :\implies \sf a \: = \dfrac{15}{10} \\ \\ :\implies \sf a \: = 1.5 \: ms^{-2} \\ \\ :\implies \sf Acceleration \: = 1.5 \: ms^{-2} \\ \\ {\pmb{\sf{Henceforth, \: converted!}}}$