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2 years ago

Choose the correct answer

Physics

1 answer:

irina1246 [14]2 years ago

6 0

Answer:

The average velocity has magnitude = 10 km/h , direction: east

Explanation:

In order to find the average velocity of the car we need to know the final and initial positions, and the time that took to get from one to the other.

Notice that since its movement was 60 km straight east and then from there 40 km straight west, the car is positioned at 20 km to the east of its initial departure point. therefore the vector change in position is a vector 20 km in magnitude, and direction towards the east.

Since it took the car a total of 1.33 hours plus 0.67 hours to reach its final position, the total time elapsed is: 1.33 + 0.67 hours = 2 hours.

Then,the velocity vector has magnitude; 20 km / 2 hours = 10 km/hour

As we mentioned above. the direction of the velocity vector is east.

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If the window is 11 m above the ground, find the time the stone is in flight.

rjkz [21]

d=vi*t+(1/2)gt²

d=11 m
g=9.8 m/s²
vi=0 m/s

11 m=0 m/s*t+(1/2)9.8 m/s²t²
11 m=4.9 m/s²t²
t²=11 m / 4.9 m/s²
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Answer:

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2 years ago

A car is driving away from a crosswalk. The formula d = t 2 + 2 t expresses the car's distance from the crosswalk in feet, d , i

Ede4ka [16]

Answer:

1) No, the car does not travel at constant speed.

2) V = 9 ft/s

3) No, the car does not travel at constant speed.

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Explanation:

In order to know if the car is traveling at constant speed we need to derive the given formula. That way we get speed as a function of time:

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