Question

What will be the final speed of a car that enters a highway at 8 meters per second and accelerates at 3 meters per second squared for 56 meters?

a) 18 m/s
b) 20 m/s
c) 22 m/s
d) 26 m/s

Answer 1

Using the kinematic equation v^2 = u^2 + 2as, where u=8 m/s, a=3 m/s², and s=56 m, we find that the final speed of the car is 20 m/s.

Step-by-step explanation:

The question asks about the final speed of a car that accelerates over a certain distance. To find the final speed, we will use the kinematic equation that does not require time:

v^2 = u^2 + 2as,

where:

• v is the final velocity,
• u is the initial velocity (8 m/s in this case),
• a is the acceleration (3 m/s² in this case),
• s is the distance (56 m in this case).

Plugging the given values into the equation:

v^2 = 8^2 + 2*3*56

v^2 = 64 + 336

v^2 = 400

v = sqrt(400)

v = 20 m/s

Therefore, the final speed of the car is 20 m/s.