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A Porsche challenges a Honda to a 200-m race.Because the Porsche's acceleration of 3.5 m/s2 is larger than the Honda's 3.0 m/s2, the Honda gets a 1.0 s head start.

Who wins and by how many seconds?

Respuesta :

Answer:

Honda won by 0.14 s

Explanation:

We are given that

Distance =S=200 m

Initial velocity of Honda=u=0m/s

Initial velocity of Porsche=u'=0m/s

Acceleration of Honda=[tex]3.0m/s^2[/tex]

Acceleration of Porsche's=[tex]3.5m/s^2[/tex]

Time taken by Honda  to start=1 s

[tex]s=ut+\frac{1}{2}at^2[/tex]

Substitute the values

[tex]200=0(t)+\frac{1}{2}(3)t^2[/tex]

[tex]200=\frac{3}{2}t^2[/tex]

[tex]t^2=\frac{200\times 2}{3}=\frac{400}{3}[/tex]

[tex]t=\sqrt{\frac{400}{3}}=11.55s [/tex]

Time taken by Honda=11.55 s

Now, time taken by  Porsche

[tex]200=\frac{1}{2}(3.5)t^2[/tex]

[tex]t^2=\frac{200\times 2}{3.5}[/tex]

[tex]t=\sqrt{\frac{400}{3.5}}=10.69 s[/tex]

Total time taken by Porsche=10.69+1=11.69 s

Because it start 1 s late

Time taken by Honda is less than Porsche .Therefore, Honda won and

Time =11.69-11.55=0.14 s

Honda won by 0.14 s

The Honda will finish the race first by 0.1 s.

The given parameters:

  • Distance, d = 200 m
  • Acceleration of the Porsche = 3.5 m/s²
  • Acceleration of the Honda, = 3.0 m/s²

Let the initial speed of each car = 0

The time of motion of the cars is calculated as follows;

[tex]s = v_0t + \frac{1}{2} at^2\\\\ s = 0 + \frac{1}{2} at^2\\\\ s = \frac{1}{2} at^2\\\\ t = \sqrt{\frac{2s}{a} } \\\\ [/tex]

The time for Porsche;

[tex]t_p = \sqrt{\frac{2s}{a} } \\\\ t_p = \sqrt{\frac{2 \times 200}{3.5} } \\\\ t_p = 10.7 \ s[/tex]

The time for Honda;

[tex]t_H = \sqrt{\frac{2s}{a} } - 1 \ s\\\\ t_H = \sqrt{\frac{2\times 200}{3} }\ - 1\ s\\\\ t_H = 10.6 \ s[/tex]

Thus, the Honda will finish the race first by 0.1 s.

Learn more about time of motion here: https://brainly.com/question/2364404