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2 years ago

9

A dog accelerates at 1.50 m/s2 to reach a velocity of 13.5 m/s while covering a distance of 49.3 m. What was his initial velocit

y?

1 answer:

vovangra [49]2 years ago

7 0

Let <em>v</em> be the dog's initial velocity. Then

(13.5 m/s)^2 - <em>v</em> ^2 = 2 (1.50 m/s^2) (49.3 m)

==> <em>v</em> ^2 = (13.5 m/s)^2 - 2 (1.50 m/s^2) (49.3 m)

==> <em>v</em> = √((13.5 m/s)^2 - 2 (1.50 m/s^2) (49.3 m))

==> <em>v</em> ≈ 5.86 m/s

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1 year ago

A car with a mass of 710 kg is traveling at 37 km/hr. It accelerates to a speed of 120 km/hr in 12.6 seconds. What is the net fo

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A river flows with a speed of 0.600 m/s. A student first swims upriver 0.500 km, then turns around and returns to his starting p

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Answer:

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c) Because of proportions

Explanation:

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Time upriver is calculated with the net speed of student and 0.500 km:

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(Becareful with units 0.5 km= 500m) Similarly of downriver:

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2 years ago