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inn [45]
3 years ago
9

If a rock weighing 2,200 N is dropped from a height of 15 m, what is its kenetic energy just before it hits the ground

Physics
1 answer:
ycow [4]3 years ago
7 0

Kinetic energy of the rock just before it hits the ground=KE=33000 J

Explanation:

Weight= 2200N

mg=2200

m(9.8)=2200

m=224.5 kg

initial velocity=0

final velocity =V

using kinematic equation V²=Vi²+2gh

V²=0+2 (9.8)(15)

V=17.1 m/s

now kinetic energy= 1/2 mV²

KE= 1/2 (224.5)(17.1)²

KE=33000 J

Thus the kinetic energy of the rock just before it hits the ground=33000 J

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Answer:

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The solution procedure can be found in the attachment below.

Explanation:

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In the solution as can be found below, the expression to calculate the range for any launch angle theta was first derived and then the required angles calculated from the equation by substituting the values of the the given quantities.

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