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**1. Homework Statement**

A 125 - G arrow is shot vertically upwards with a Vi of 28/ms. Assuming a 20% loss in Mechanical Energy while ascending, what maximum height above the position it was shot does it reach?

**2. Homework Equations**

Vi= 28m/s

Vf= O m/s

D= ?

a= -9.8 m/s

Vf^2= Vi^2 + 2aD

Eg = mgh

Ek = 1/2mv^2

EM = Eg + Ek (not sure}

**3. The Attempt at a Solution**

I did not really understand this question but I tried to make a solution using what I know.

I tried using one of the 5 equations but that did not help so i tried using work and energy equations.

So i did Ek first

Ek= 1/2 mv ^2

Ek = 1/2 (0.125 kg) (28 m/s)^2

Ek = 98 J

Next I tried finding the Eg

Eg = Ek x 0.70

(30% loss of mechanical energy, this is what i am thinking)

Eg = 68.6 J

Eg = mgh

Eg= 0.125 (9.8) h

68.6 = 1.225 h

68.6/1.225= h

h= 55.51 m

Did I do this question right or wrong? I am very confused. Some help would be appreciated!