- #1
barthayn
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Homework Statement
An object is pushed along a rough horizontal surface and released. it slides for 10.0s before coming to rest and travels a distance of 0.2m during the last 1.0s of its slide. Assuming the acceleration to be uniform throughout
a) How fast was the object traveling upon release?
b) How fast was the object traveling when it reached the half way position in its slide?
vf = 0m/s
vi = ?
d1 = ?
d2 = 0.2m
a = ?
t = 10s
Homework Equations
a = Δv/Δt
Δd = vΔt = ((Vi+Vf)/2)Δt
vf = Δt-1/2a(Δt)2
Δd = vfΔt-1/2a(Δt)2
The Attempt at a Solution
a = -0.4/1
a = -0.4m/s2
Δd = (0.4(100))/2
Δd = 40/2
Δd = 20 m
vi2 = 0-(-0.2)(20.2)
vi2 = 4.04m2/s2
vi = 2.009m/s
Therefore the object was traveling at 2.009 m/s when first released.
For part b, I do not know where to begin. The acceleration is -0.4m/s2, as founded in the first part. But I do not know how to apply the information because I get a negative answer for the final velocity for the half way point.