How Do You Calculate Acceleration and Total Distance in a Car's Journey?

[Xidike]

Homework Statement

A Car starts from the rest, accelerate and reaches the speed of 72Km/h in 20s. It keeps the speed for 5 minutes and then applies brakes and stops after covering a distance of 100m.
find:
Acceleration, Declaration, Total Distance Covered And Total Time Used..
please help me,

Homework Equations

The Attempt at a Solution

 

[Ibix]

What have you tried doing?

 

[yands]

A car start from rest accelerate .
Is it constant acceleration? And you have to show us some of your work

 

[CWatters]

Show us some of your ideas on how to approach the problem even if you think they are wrong.

 

[Nickie]

I would approach this problem by first defining the variables involved. Velocity, or speed, is a measure of how fast an object is moving and is typically given in units of distance per time (e.g. km/h). Acceleration, on the other hand, is a measure of how quickly an object's velocity is changing and is typically given in units of distance per time squared (e.g. km/h^2).

Using this information, we can determine the acceleration of the car by dividing the change in velocity by the change in time. In this case, the car starts from rest and reaches a final velocity of 72 km/h in 20 seconds. Therefore, the acceleration can be calculated as:

Acceleration = (Final Velocity - Initial Velocity) / Time
= (72 km/h - 0 km/h) / (20 s)
= 3.6 km/h^2

Next, we can calculate the deceleration, or negative acceleration, when the car applies brakes and stops after covering a distance of 100m. Since the car was traveling at a constant speed of 72 km/h for 5 minutes, or 300 seconds, the initial velocity for this part of the journey is 72 km/h and the final velocity is 0 km/h. Therefore, the deceleration can be calculated as:

Deceleration = (Final Velocity - Initial Velocity) / Time
= (0 km/h - 72 km/h) / (300 s)
= -0.24 km/h^2

To find the total distance covered by the car, we can add the distance traveled during acceleration and deceleration. During acceleration, the car covers a distance of:

Distance = Initial Velocity * Time + (1/2) * Acceleration * Time^2
= 0 km/h * 20 s + (1/2) * 3.6 km/h^2 * (20 s)^2
= 360 m

During deceleration, the car covers a distance of 100 m. Therefore, the total distance covered is 360 m + 100 m = 460 m.

Lastly, to find the total time used, we can add the time taken for acceleration (20 s) and the time taken for deceleration (300 s), which gives a total time of 320 seconds.

In conclusion, the acceleration of the car was 3.6 km/h^2, the dec