How long in seconds does it take for a car accelerating at 3.5m/s2 to go from rest to 120km/hr
First you need to convert the final speed to meters per second. I assume you know how to do that.
Vfinal = 120 km/h = 33.33 m/s
The acceleration rate is a = 3.5 m/s^2
Time required = Vfinal/a = 33.33/3.5
= 9.5 seconds.
To find the time it takes for a car to accelerate from rest to a certain velocity, we can use the following formula:
v = u + at
Where:
v = final velocity
u = initial velocity (which is zero in this case since the car is at rest)
a = acceleration
t = time
We need to convert the final velocity from km/hr to m/s to match the units of acceleration. Here's the conversion:
120 km/hr * (1000 m / 1 km) * (1 hr / 3600 s) = 33.33 m/s (approximately)
Now we can rearrange the formula to solve for time (t):
t = (v - u) / a
Plugging in the values, we get:
t = (33.33 m/s - 0) / 3.5 m/s²
t ≈ 9.52 seconds
So, it takes approximately 9.52 seconds for the car to accelerate from rest to 120 km/hr.