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How do you do this and please explain+show work so I understand?

How do you do this and please explain+show work so I understand?-example-1

1 Answer

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Step-by-step explanation:

For each point:

PE = mgh

KE = ½ mv²

ME = PE + KE

Since energy is conserved, ME will be constant.

I'll be using g = 10 m/s².

A. PE = (100 kg) (10 m/s²) (102 m) = 102,000 J

KE = ½ (100 kg) (0 m/s)² = 0 J

ME = 102,000 J

B. KE = ½ mv²

18,000 J = ½ (100 kg) v²

v = 60 m/s

ME = 102,000 J

PE = ME − KE = 84,000 J

(100 kg) (10 m/s²) h = 84,000 J

h = 84 m

C. KE = ½ (100 kg) (29 m/s)² = 42,050 J

ME = 102,000 J

PE = ME − KE = 59950 J

(100 kg) (10 m/s²) h = 59950 J

h = 59.95 m

d. PE = (100 kg) (10 m/s²) (60 m) = 60,000 J

ME = 102,000 J

KE = ME − PE = 42,000 J

½ (100 kg) v² = 42,000 J

v = 29.0 m/s

E. PE = (100 kg) (10 m/s²) (0 m) = 0 J

ME = 102,000 J

KE = ME − PE = 102,000 J

½ (100 kg) v² = 102,000 J

v = 45.2 m/s

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