Question

An object starting from rest travels with an acceleration of 5m/s what will be it's velocity after 3s?

Answer 1

EXPLANATION.

• GIVEN

object is start from rest = u = 0

acceleration = 5 m/s^2

time = 3 seconds

TO FIND IT'S VELOCITY.

initial speed = 0

final velocity = v

acceleration = 5 m/s^2

time = 3 seconds

From newton first equation of kinematics,

v = u + at

v = 0 + 5 X 3

v = 15 m/s

Therefore,

velocity = 15 m/s

MORE INFORMATION.

1) = Newton first equation of kinematics

$\bigstar\green{\boxed{v \: = u + at}}$

2) = Newton second equation of

kinematics

$\bigstar\green{\boxed{s \: = ut \: + \frac{1}{2}a {t}^{2}}}$

3) = Newton third equation of kinematics

$\bigstar{\green{ \boxed{{v}^{2} = u {}^{2} + 2as}}}$

Answer 2

GiveN :

• Initial velocity (u) = 0 m/s
• Acceleration (a) = 5 m/s²
• Time interval (t) = 3 s

To FinD :

• Final velocity

SolutioN :

Use 1st equation of motion :

⇒ v = u + at

⇒ v = 0 + 5 * 3

⇒ v = 0 + 15

⇒ v = 15

➜ Velocity after 3 seconds is 15 m/s