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Tarzan (mT=85.0 kg) is perched on a cliff 16.0 m above Jane. Jane is in the foreground is looking forwards. In the background, Tarzan has jumped off of a cliff and is swinging on a vine towards Jane. A red curved arrow points from Tarzan to Jane, showing the path he will swing on. Answer the three questions below, using three significant figures. Part A: What is the value of Tarzan's speed (vT) just as he gets down to Jane's level?

User Spemble
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1 Answer

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Complete Question

The complete question is shown on the first uploaded image

Answer:

Part A

The velocity of Tarzan is
v_T = 17.7 \ m/s

Part B

The percentage loss of kinetic energy is %-loss
= 61.4%

Part C

The speed would be exactly the same

Step-by-step explanation:

From the question we are told that

The mass of Tarzan is
m = 85.5 \ kg

The height of the cliff is
h = 16.0 \ m

From the law of conservation of energy


PE = KE

Where PE is the potential energy of Tarzan at the top of the cliff which is mathematically represented as


PE = mgh

KE is the kinetic energy of Tarzan as he swings toward jane and is mathematically represented as


KE = (1)/(2) mv^2_T

So


mgh = (1)/(2)m v_T^2

=>
gh = (1)/(2) v_T^2

Substituting values


9.8 * 16 = (1)/(2) v_T^2

=>
v_T = \sqrt{(9.8 * 16)/(0.5) }


v_T = 17.7 \ m/s

From the question we are told that the actual velocity of Tarzan is


v = 11 m/s

The kinetic energy at the the velocity is mathematically represented as


KE_A = (1)/(2) m v^2

Substituting values


KE_A = (1)/(2) (85) * 11^2


KE_A = 5142.5 J

The kinetic energy at
v_T is


KE = (1)/(2) * 85 * 17.7^2

=>
KE = 13314.83\ J

Now the percentage loss of kinetic energy is mathematically evaluated as

%-loss
= (KE - KE_A)/(KE) * 100

substituting values

%-loss
= (13314.83 - 5142.5)/(13314.83) * 100

%-loss
= 61.4%

The mass of Tarzan does not affect the speed because looking at this equation


gh = (1)/(2) v_T^2

We see that the velocity of Tarzan is not dependent on the mass of Tarzan

Tarzan (mT=85.0 kg) is perched on a cliff 16.0 m above Jane. Jane is in the foreground-example-1
User Rahul Modi
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