Question

A car with an initial velocity of 10.8 km/h experiences an acceleration of - 0.82 m/s²

for 2.0 s.
(a) Calculate the car’s final speed.
(b) What is the car’s displacement?

Answer 1

The car's final speed is 1.36 m/s and its displacement is 5.36 m.

Step-by-step explanation:

(a) To calculate the car's final speed, we can use the equation:

Final velocity = initial velocity + (acceleration x time)

Plugging in the values:

Final velocity = 10.8 km/h + (-0.82 m/s² x 2.0 s)

Converting km/h to m/s: Final velocity = (10.8 km/h * 1000 m/km) / (3600 s/h) = 3.0 m/s

Calculating the final velocity:

Final velocity = 3.0 m/s + (-0.82 m/s² x 2.0 s) = 1.36 m/s

(b) To calculate the car's displacement, we can use the equation:

Displacement = (initial velocity x time) + (0.5 x acceleration x time²)

Plugging in the values:

Displacement = (10.8 km/h * 1000 m/km) / (3600 s/h) * 2.0 s + (0.5 x -0.82 m/s² x (2.0 s)²)

Calculating the displacement:

Displacement = 3.0 m/s * 2.0 s + (0.5 x -0.82 m/s² x 4.0 s²) = 5.36 m.