Question

A car start from rest and moves with constant acceleration of 4 metre per second square for 30 seconds then the Breakers are applied and the car come to rest under 16 second find the maximum velocity attained by car

Answer 1

As per the question , the car starts from rest and moves with constant acceleration for a certain time. After that , the brakes are applied and the car comes to rest under a particular time interval.

After reading this we can easily understand that the maximum velocity of the car is reached at the end of the constant acceleration. In other words , we can say that maximum velocity is reached at the end of 30 seconds.

Simply applying the equation of kinematics :

$v_{max} = u + at$

$= > v_{max} = 0 + (4 \times 30)$

$= > v_{max} = 120 \: m {s}^{ - 1}$

So final answer is :

Maximum velocity is 120 m/s

Answer 2

Aɴꜱᴡᴇʀ

The maximum velocity of the body = 130 m/s

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Gɪᴠᴇɴ

✭ Initial velocity (u) = 0 m/s

✭ Acceleration (a) = 4 m/s²

✭ Time (t) =30 seconds

✭ Final velocity (v) = 0 m/s

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Tᴏ ꜰɪɴᴅ

➤ The maximum Velocity attained by the car?

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Sᴛᴇᴘꜱ

❍ Actually here let us just consider the scenario just before the car stops, that is let us not considered that the car finally stops.

➳ So then the maximum velocity becomes the final velocity and so to find our answer let's use The first law of motion.

Substituting the given values,

$\large \tt \leadsto{}v = u + at \\ \\ \large \tt \leadsto{}v = 0 + 4 \times 30 \\ \\ \large \tt \pink{ \leadsto{}v = 120 \: m/s}$

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