A car accelerates from rest at 4.9 m/s2.
How much time does it need to attain a
speed of 6 m/s?
vf=at solve for time t.
To find the time it takes for the car to reach a speed of 6 m/s, we can use the formula for acceleration:
acceleration (a) = change in velocity (Δv) / time (t)
In this case, the initial velocity (u) is 0 m/s (rest) and the final velocity (v) is 6 m/s. The acceleration (a) is given as 4.9 m/s².
Substituting the values into the formula, we have:
4.9 m/s² = (6 m/s - 0 m/s) / t
To solve for time (t), we rearrange the equation:
t = (6 m/s - 0 m/s) / 4.9 m/s²
To determine the time it takes for the car to attain a speed of 6 m/s, we can use the equation of motion:
v = u + at
where:
v = final velocity (6 m/s in this case)
u = initial velocity (0 m/s since the car starts from rest)
a = acceleration (4.9 m/s^2 given in the problem)
t = time
Rearranging the equation, we have:
t = (v - u) / a
Substituting the given values:
t = (6 m/s - 0 m/s) / 4.9 m/s^2
t = 6 m/s / 4.9 m/s^2
t ≈ 1.22 seconds
Therefore, the car needs approximately 1.22 seconds to attain a speed of 6 m/s.