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3 years ago

7

At the instant the traffic light turns green, an automobile starts with a constant acceleration a of 2.70 m/s2. At the same inst

ant a truck, traveling with a constant speed of 9.50 m/s, overtakes and passes the automobile. (a) How far beyond the traffic signal will the automobile overtake the truck

1 answer:

kifflom [539]3 years ago

3 0

Answer:

66.85 m

Explanation:

We are given that

Acceleration ,a= $2.7m/s^2$

Speed of truck, v=9.5 m/s

We have to find the distance beyond which the traffic signal will the automobile overtake the truck.

Initial speed of automobile, u=0

We know that

$s=ut+\frac{1}{2}at^2$

Using the formula

$s=0+\frac{1}{2}(27)t^2=\frac{27}{2}t^2$

For constant speed

Acceleration, a=0

Again

$s=vt+0=9.5t$

$9.5t=\frac{27}{2}t^2$

$t=\frac{9.5\times 2}{2.7}=7.037s$

Substitute the value of t

$x=9.5(7.037)=66.85m$

Hence, the distance beyond which the traffic signal will the automobile overtake the truck=66.85 m

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