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3 years ago

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A car travels in a straight line covering a total distance of 90.0 miles in 60.0 minutes. Which one of the following statements

concerning this situation is necessarily true?
A) The velocity of the car is constant.
B) The acceleration of the car must be non-zero.
C) The first 45 miles must have been covered in 30.0 minutes.
D) The speed of the car must be 90.0 miles per hour throughout the entire trip.
E) The average velocity of the car is 90.0 miles per hour in the direction of motion.

1 answer:

andrezito [222]3 years ago

7 0

Answer:

E) The average velocity of the car is 90.0 miles per hour in the direction of motion.

Explanation:

Given;

distance covered by the car, d = 90 miles

time taken, t = 60 minutes = 1 hour

The average velocity of the car is given by change in displacement per change in time;

V = Δd / Δt

$V = \frac{x_f - x_o}{t_f -t_o} = \frac{90-0}{1-0} \\\\V = 90 \ miles/hour$

Therefore, the average velocity of the car is 90.0 miles per hour in the direction of motion.

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There is a missing data in the text of the problem (found on internet):
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