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3 years ago

C. A 75 lb (34 kg) boy falls out of a tree from a height of 10 ft (3 m). (3 points)

Chemistry

1 answer:

KatRina [158]3 years ago

7 0

(I) kinetic energy of the boy when he hits the ground =potential energy

I. e ½mv²=mgh where g is 10ms-²

m=34kg, g=10ms² , h=3m

=34×10×3

=1020j

(i i) v²=u²+2gh

v²=0²+2×10×3

= 60

v=sqrt of 60

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