- #1
alexas
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Homework Statement
A 1.50 kg steel block is at rest on a steel table. A horizontal string pulls on the block. The coefficient of static friction of dry steel on steel is Uk=.800, the coefficient of kinetic friction of dry steel on steel is Uk=.600, and the coefficient of kinetic friction of lubricated steel on steel is UkLUBE=.050
What is the minimum string tension needed to move the block?
If the string tension is 19.0 N, what is the block's speed after moving 1.30 m?
If the string tension is 19.0 N and the table is coated with oil, what is the block's speed after moving 1.30 m?
Homework Equations
F = (Uk)mg
The Attempt at a Solution
What is the minimum string tension needed to move the block?
F = (.8)(1.5)(9.8) = 11.76
F = 11.8
If the string tension is 19.0 N, what is the block's speed after moving 1.30 m?
Since we know we need at least 11.8 to get it to move, we have an additional 7.2N
So i figured...
F = ma
7.2 N = (1.5kg)a
a = (7.2)/(1.5)
a = 4.8 m/(s^2)
Anyways, I am a little confused on what to do after i have the acceleration.
If the string tension is 19.0 N and the table is coated with oil, what is the block's speed after moving 1.30 m?
I figure i could approach this the same was as the second question but i would basically just need to recompute the minimal tension required to move it.