👤

A car travelling on a straight road initially at 54 km/h accelerates for 2.3 s at a constantacceleration of 8.2 m/s2. What is the car's final speed, in m/s?(Hint: You must first convert 54 km/h to m/s.)

Answer :

Given:

The initial speed of the car is,

[tex]u=54\text{ km/h}[/tex]

The acceleration is,

[tex]a=8.2\text{ m/s}^2[/tex]

The time for which the car is travelling with acceleration is,

[tex]t=2.3\text{ s}[/tex]

To find:

The car's final speed

Explanation:

The initial speed of the car is,

[tex]\begin{gathered} u=54\text{ km/h} \\ =\frac{54\times1000}{3600}\text{ m/s} \\ =15\text{ m/s} \end{gathered}[/tex]

The final speed of the car is,

[tex]v=u+at[/tex]

Substituting the values we get,

[tex]\begin{gathered} v=15+8.2\times2.3 \\ =33.9\text{ m/s} \end{gathered}[/tex]

Hence, the final speed is 33.9 m/s.