Question

A car is running with the velocity of 72 km/h. What will be its velocity after 5 s if its acceleration is -2m/s^2?

Please solve it in steps. I really need to know it.

Answer 1

Answer :-

Given :-

• Initial velocity = 72 km/h
• Time = 5 seconds
• Acceleration = -2 m/s²

To Find :-

• Final velocity

Solution :-

Converting the unit of initial velocity to m/s :-

→ 72 km/h = 72 × 5 / 18 = 20 m/s

Substituting the value in 1st equation of motion :-

v = u + at

where

• v is final velocity
• u is initial velocity
• a is acceleration
• t is time

→ v = 20 + ( - 2 ) × 5

→ v = 20 + ( - 10 )

→ v = 20 - 10

→ v = 10

Final velocity = 10 m/s

Answer 2

A N S W E R :

• The final velocity is 10m/s.

Given :

• Initial velocity = 72 km/h

• Time = 5 seconds

• Acceleration = 2m/s²

To find :

• Find the velocity ?

Solution :

• Converting the unit of initial velocity to m/s

=> 72 km/h = 72 × 5/18 = 20m/s (equation 1)

• Putting the given values in (1) equation

• Motion

As we know that,

Formula Used :

★ v = u + at

So,

• v is finall velocity
• u is initial velocity
• a is accelerates
• t is time

=> v = 20 + (-2) × 5

=> v = 20 + (-10)

=> v = 20 - 10

=> v = 10

Hence,

• The final velocity is 10m/s.