Centripetal Acceleration/Rotational Motion HW Problem

AI Thread Summary
A block on a smooth sphere of radius 1m slides down due to gravity until it leaves the surface. The equations used include mgcosθ + N = mv^2/R, with N set to zero, leading to v^2 = Rgcosθ. The work-energy theorem is applied, resulting in the equation Rgcosθ = 2gR(1-cosθ). Solving for cosθ gives 3cosθ = 2, leading to cosθ = 2/3. The final speed at which the block leaves the surface is calculated as approximately 2.556 m/s, with a note of uncertainty regarding the initial equation's formulation potentially affecting the result.
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A block sits at the top of a smooth sphere of radius 1m. Suddenly, under the
force of gravity, It begins to slide down the surface of the sphere until it leaves the
surface. At what speed does it leave the surface?

mgcosθ + N = mv^2/R
But N =0
v^2 = Rgcosθ
V^2 = gcosθ
speed = v = ( 9.8cosθ)^0.5
Now,
from work energy theorem,
0.5mv^2 - 0 = mgR(1-cosθ)
Rgcosθ = 2gR(1-cosθ)
cosθ = 2(1-cosθ)
3cosθ = 2
cosθ = 2/3
Now
SPeed = v = (9.8 x 2/3)^0.5 = 2.556 m/s

I am unsure if there's supposed to be a 1/2 in front of the mv^2/R on the first line of my work, which would change the final value to 6.32 m/s
 
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sorry i meant 3.62 for the new value lol
 
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