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andriy [413]
3 years ago
7

A stone is thrown straight up from the roof of an 80 ft building. the height, in feet, of the stone at any time t, in seconds, m

easured from the ground is given by ℎ(????) = −16???? 2 + 64???? + 80. what is the maximum height the stone reaches?
Physics
1 answer:
julsineya [31]3 years ago
8 0

Answer:

144 ft

Explanation:

h(t) = -16t² + 64t + 80

The maximum height is at the vertex.  We can find the vertex of a parabola using -b / (2a):

t = -64 / (2×-16)

t = 2

The vertex is at 2 seconds.  The height of the stone at this time is:

h(2) = -16(2)² + 64(2) + 80

h(2) = 144

The maximum height is 144 feet.

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A circular coil of radius 5.0 cm and resistance 0.20 Ω is placed in a uniform magnetic field perpendicular to the plane of the c
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Answer:

Explanation:

Given that,

Assume number of turn is

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Substituting the values given

I = 10×1× 7.85 ×10^-3×exp(-20×2)/0.2

I = 1.67 × 10^-18 A

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Answer:

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I hope this helped you...  

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