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ale4655 [162]
2 years ago
10

If a ball with an original velocity of 0 is dropped from a tall structure and takes 7 Seconds to hit the ground what velocity do

es the ball have when it reaches the ground
A. 156.8

B. 240.1

C. 68.6

D. 34.3
Physics
1 answer:
MrMuchimi2 years ago
5 0

Gravity adds 9.8 m/s to the downward speed of a falling object every second. (On Earth.)

In 7 seconds, gravity adds (7 x 9.8 m/s) = <em>68.6 m/s</em> to the downward speed of a falling object.

(IF air resistance has no effect on the object.)

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c = fλ

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a. As λ increases, f decreases and ΔE decreases.
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b. As λ increases, f increases and ΔE increases.
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c. As λ increases, f increases and ΔE decreases.
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Answer: 
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3 0
3 years ago
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Answer:

3.25 seconds

Explanation:

It is given that,

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i.e.

-16t^2+50t+7=0

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7 0
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Red clothes look red  because they REFLECT the red light, and absorb light of other colors.

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