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scZoUnD [109]
3 years ago
10

A ski jumper starts at the top of a 400m high hill before skiing down to the bottom. If the ski jumper has a mass of 75kg how mu

ch potential energy would they have at the beginning of the their motion?
A. 3920 J
B. 30,000 J
C. 735 J
D. 294,000 J
Physics
1 answer:
alekssr [168]3 years ago
6 0

Answer:B. 30,000 J

Explanation:

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Explanation:

(a)

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(b)

Immediately prior to the explosion, the ball is at the maximum height.  Here, the vertical velocity is 0 m/s, and the horizontal velocity is constant at 25 m/s.

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(c)

Momentum is conserved before and after the explosion.

In the x direction:

m vx = ma vax + mb vbx

m (25) = (⅓ m) (0) + (⅔ m) (vbx)

25m = (⅔ m) (vbx)

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And in the y direction:

m vy = ma vay + mb vby

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And the horizontal velocity will stay constant.

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Answer with Explanation:

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We know that gravitational force=\frac{GmM}{r^2}

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\frac{M}{m}=4

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Answer:

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