Question

A Car is running with the velocity of 72km/hr. What will be the velocity after 5 seconds,if its accleration is -2m/sec?

Answer 1

Given :

• Initial Velocity = 72 km/hr
• Time Taken = 5 seconds.
• Acceleration = -2m/s

To Find :

• Final Velocity of the car.

Solution :

$\longmapsto\tt{Initial\:Velocity(u)=72km/hr=20m/s}$

Using 1st Equation of Motion :

$\longmapsto\tt{v=u+at}$

Putting Values :

$\longmapsto\tt{v=20+(-2)\times{5}}$

$\longmapsto\tt{v=20+(-10)}$

$\longmapsto\tt{v=20-10}$

$\longmapsto\tt\bold{v=10m/s}$

So , The Final Velocity of the car is 10m/s...

_______________________

Three Equations of Motion :

• v = u + at
• s = ut + 1/2 at²
• v²-u²=2as

_______________________

Answer 2

✔ Given :-

• Initial Velocity = 72km/hr = 20m/s

• Acceleration = -2m/s²

• Time = 5 seconds.

✔ To Find :-

• Final Velocity.

✔ Solution :-

We can Apply First Equation Of Kinematics,

$\Large\boxed{\sf{v = u + at}}$

Put the values.

➝ $\rm{v = 20 + -2(5)}$

➝ $\rm{v = 20 - 10}$

➝ $\underline{\boxed{\bf{\red{v = 10m/s}}}}$

Hence, Final Velocity = 10m/s.