Question

velocity of a car started from rest reaches 24 m/s in 4s.what are the initial velocity and the final velocity of the car? Calculate its acceleration?​

Answer 1

Given :-

• Velocity of a car started from rest reaches 24 m/s in 4s

To find :-

• Initial velocity
• Final velocity
• Acceleration

Solution :-

• Initial velocity = 0 {started from rest}

• Final velocity = 24 m/s

• Time = 4s

According to first equation of motion

→ v = u + at

Where " v " is final velocity, " u " is initial velocity, " a " is acceleration and " t " is time taken.

• Put the values

→ 24 = 0 + a × 4

→ 24 = 4a

→ a = 24/4

→ a = 6 m/s²

Hence,

• Acceleration of car is 6 m/s²

More to know

• s = ut + at² { second equation of motion }

• v² = u² + 2as { Third equation of motion }

• Negative value of acceleration is known as retardation

Answer 2

ɢɪᴠᴇɴ :-

• Velocity=24
• Time = 4s

ᴛᴏ ꜰɪɴᴅ :-

• Acceleration

ᴅɪᴀɢʀᴀᴍ:-

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ꜱᴏʟᴜᴛɪᴏɴ :-

Initial velocity = 0

Final velocity = 24 m/s

Time = 4s

We know that,

• According to first equation of motion for constant acceleration,

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

Here,

" v " is final velocity

" u " is initial velocity

" a " is acceleration

" t " is time taken.

So,

24 = 0 + a × 4

24 = 4a

a = $\dfrac{24}{4}$

a = 6 m/s²

$\begin{lgathered}\begin{lgathered}\begin{lgathered}:\implies{\boxed{\frak{\green{a=\;6\;m/s^2}}}}\;\bigstar\\ \\\end{lgathered}\end{lgathered}\end{lgathered}$

Hence, the acceleration of car is 6 m/s²

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