Question

 A train starts from rest and accelerates uniformly at the of 5 m/s2 for 45 second .Calculate its velocity . 

(A) 25 m/s

(B) 10 m/s

(C) 5 m/s

(D)5 m/s

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Answer 1

✬ Final Velocity = 225 m/s ✬

Explanation:

Given:

• Initial velocity is 0 m/s.
• Acceleration produced by truck is 5 m/s².
• Time is 45 seconds.

To Find:

• What is the final velocity ?

Formula to be used:

• v = u + at

Solution: Let v be the final velocity of truck.

We have

• u = 0 m/s
• v = ?
• t = 45 seconds
• a = 5 m/s²

Putting the values on formula.

$\implies{\rm }$ v = u + at

$\implies{\rm }$ v = 0 + 5(45)

$\implies{\rm }$ v = 0 + 225

$\implies{\rm }$ v = 225

Hence, the velocity of train after 45 seconds will be 225 m/s.

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If we take time = 5 second then the answer will match from given option.

$\implies{\rm }$ v = 0 + 5(5)

$\implies{\rm }$ v = 0 + 25

$\implies{\rm }$ v = 25 m/s

Answer 2

✒ANSWER:-

OPTION (A) IS CORRECT ✔✔

✒EXPLANATION:-

${ \mathtt{ \underline{ \underline{Given}}}}$

• u=0

• a=5m/sec^2

• t=5sec

${ \mathtt{ \underline{ \underline{To \: Find}}}}$

v=??

${ \mathtt{ \underline{ \underline{Solution}}}}$

We know that,

${ \bf{v = u + at}}$

Where,

${ \mathtt{ \pink{v = final \: velocity}}}$

${ \mathtt{ \pink{u = initial \: velocity}}}$

${ \mathtt{ \pink{a = acceleration}}}$

${ \mathtt{ \pink{t = time}}}$

By putting the given values in the formula we get,

$⟹v = 0 + 5 \times 5$

$⟹25m \: per \: sec$

So the velocity is 25 m/sec.

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