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sona1177
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Homework Statement
A crate pushed along the floor with velocity Vi slides a distance d after the pushing force is removed.
a)If the mass of the crate is doubled but the initial velocity is not changed, what distance does the crate slide before stopping? Explain.
b) If the initial velocity of the crate is doubled to 2vi but the mass is not changd, what distance does the crate slide before stopping? Explain.
Homework Equations
F=ma
F=max (object is moving horizontally)
The Attempt at a Solution
a) Fnetx=nx + wx + tx where t stands for the pushing force, n is the normal force, and w is weight pulling down on the object.
nx=0
wx=0
Tx=max
Tx/m=ax
Kinetics Equation:
V2=Vi2 + 2a(Xf-Xi)
0=Vi2 + 2a(Xf-Xi)
-Vi2=2(Tx/m)d (where d stands for Xf- Xi)
Doing algebra: d=-mVi2/ (2*Tx) (in this equation only the Vi is squared, in the denominator, the answer is (2 times Tx). I hope that is clear.
b) -m * 2 * Vi2/2 *Tx (in this equation its 2 times the initial velocity squared divided by 2 times Tx) therefore the 2's cancel out and I get the same answer as I did for part a -m* Vi2/Tx=d
I hope this makes sense. Is my work and answer correct? I'm not sure if this was the answer the book was looking for. Thank you kindly for taking the time to help me.