Question

At highway speeds, a particular automobile is capable of an acceleration of about 2.0 m/s2 . Part A At this rate, how long does it take to accelerate from 75 km/h to 110 km/h ?

Answer 1

Answer:

Time taken, t = 4.86 seconds

Explanation:

Given that,

Acceleration of a particular automobile, $a=2\ m/s^2$

Initial speed of the automobile, u = 75 km/h = 20.83 m/s

Final speed of the automobile, v = 110 km/h = 30.55 m/s

We need to find the time taken to accelerate from u to v. Let t is the time taken. It can be calculate as :

$t=\dfrac{v-u}{a}$

$t=\dfrac{30.55-20.83}{2}$

t = 4.86 seconds

So, the time taken by the automobile is 4.86 seconds. Hence, this is the required solution.

Answer 2

Answer:

4,86 seconds

Explanation:

To answer this we first have to convert the velocity from km/hr to m/s, we will use the next conversion ratios:

$\frac{75 km}{1 hr}(\frac{1000m}{1 km})(\frac{1 hour}{3600 seconds})=\frac{20,83m}{1 second}$

$\frac{110 km}{1 hr}(\frac{1000m}{1 km})(\frac{1 hour}{3600 seconds})=\frac{30,55m}{1 second}$

So we have both distances, now we have to calculate the time thatit would take for the automobile to accelerate to 30,55 m/s at 2 m/s^2 using the formula for acceleration:

$Acc=\frac{Vf-Vo}{time} \\Time=\frac{Vf-Vo}{Acc}\\ Time=\frac{30,55-20,83}{2,0}\\ Time=\frac{9,72}{2}\\ Time=4,86 seconds$

The time that it would take a particular car to change its velocity from 75km/hr to 110 km/hr at an acceleration rate of 2 m/s will be 4,86 seconds.