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Plz. help ) An auto accelerates forward from 7.0 m/s at a uniform

0.71 m/s?. It travels a distance of 1033 m while
accelerating

(a) How fast is the auto moving just as it is traveled
the 1033 m?

(b) How many seconds did it take to travel the 1033 m?​

User PieCot
by
5.2k points

1 Answer

3 votes

Answer:

The auto is moving at 38.9 m/s

The auto took 45 seconds to travel the 1033 m

Step-by-step explanation:

Constant Accelerated Motion

it's a type of motion in which the velocity of an object changes uniformly in time.

The relationship between initial and final speeds is calculated by the equation:


v_f=v_o+at\qquad\qquad [1]

Where a is the constant acceleration, vo the initial speed, vf the final speed, and t the time.

Another useful equation allows us to calculate the distance x traveled by the object:


\displaystyle x=v_o.t+(a.t^2)/(2)\qquad\qquad [2]

(a)

Solving [1] for t and substituting into [2] we find the equation:


v_f^2=v_o^2+2ax

This last equation will be used to solve the first part of the problem which gives the initial speed of vo=7 m/s, the uniform acceleration as a=0.71 m/s^2 and the distance traveled as x=1033 m, thus substituting:


v_f^2=7^2+2(0.71)(1033)


v_f^2=49+1466.86=1515.86

Thus:


v_f=√(1515.86)=38.9


v_f=38.9 m/s

The auto is moving at 38.9 m/s

(b)

To calculate the time, we solve [1] for t:


\displaystyle t=(v_f-v_o)/(a)


\displaystyle t=(38.9-7)/(0.71)=45

The auto took 45 seconds to travel the 1033 m

User Gorefest
by
5.8k points