Calculating Object's Trajectory on a Circular Track

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myoplex11
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Homework Statement


A frictionless track with a loop of radius 36 cm sits on a table 0.9 meters above the ground. If a 0.15 kg object just makes the loop, how high above the table did the object start and how far from the table does it land?




Homework Equations





The Attempt at a Solution


Can you check my work
Mgh - Mg(2R) = 0.5MV^2
gh - 2gR = 0.5V^2
once i solve for V i can use a kinematics equation to figure our how far from the table it lands?
 
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I think I misunderstood question first time.
 
Last edited:
Can you check my work
Mgh - Mg(2R) = 0.5MV^2
gh - 2gR = 0.5V^2
gh-2gR = 0.5Rg
h = 2.5R = 2.5(.36m)= 0.9
for the second part to figure out how far from the table it lands:
Y = Voyt + .5gt^2
0.9 = 4.9t^2
t = 0.428571s
x = Voxt
x =((Rg)^0.5)*t
 
First part is correct. For the second part, you have put Y = 0.9 m and Vox = sqrt(Rg).
But Vox = sqrt(Rg) at the top of the loop. At that time, the object's height from ground
= table's height from ground + object's height from table
= 0.9 m + 2R
= 0.9 m + 2*0.36 m
= 1.62 m
So put Y = 1.62 m
Rest is fine.