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Studentka2010 [4]
3 years ago
15

A key falls from a bridge that is 44 m above the water. It falls directly into a model boat, moving with constant velocity, that

is 19 m from the point of impact when the key is released. What is the speed of the boat
Physics
1 answer:
Lady_Fox [76]3 years ago
6 0

The time t it takes for the key to fall 44 m is

44\,\mathrm m=\dfrac12\left(9.8\,\dfrac{\mathrm m}{\mathrm s^2}\right)t^2\implies t=3.0\,\mathrm s

(notice I'm taking the downward direction to be positive)

The boat, moving at a presumably constant speed, then has 3.0 s to travel 19 m to the point of impact, which means its speed must be

v=\dfrac{19\,\mathrm m}{3.0\,\mathrm s}=6.3\,\dfrac{\mathrm m}{\mathrm s}

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Reika [66]

Answer:

179.47m/s

Explanation:

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u1 and u2 are the initial velocities

v is the final velocity

Substitute

7750(179)+72(230) = (7750+72)v

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v= 179.47m/s

Hence the final velocity of the probe is 179.47m/s

7 0
2 years ago
20 POINTS 20 POINTS On a bright sunny day you decide to take a walk. You begin at your home and walk 1000 meters to an ice cream
Kay [80]

Answer:

A) Total Distance = 2000 m and Total displacement = 0 m

B) Average Speed = 44.44 m/min and Average Velocity = 0 m/min

C) Average Speed = 0.7407 m/s and Average velocity = 0 m/s

Explanation:

A) Distance to reach ice cream shop from home = 1000 meters

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Total distance traveled = 1000 + 1000 = 2000 metres

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B) Average speed = Total distance/total time.

Total time = 10 + 15 + 20 = 45 minutes

Since total distance = 2000 m

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Average velocity = 0/45 = 0 m/min

C) We now want answers in B to be in m/s.

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4 0
3 years ago
Weightlessness is experienced by an astronaut in space. This means that the astronaut's muscles have to be stronger to move his
just olya [345]
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4 0
3 years ago
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shepuryov [24]

Answer:

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μ = 1.33 / sinC

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μ = 1.6   Ans

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Answer:

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