Block Movement Dynamics: Solving for Time, Acceleration, and Distance

AI Thread Summary
A block of mass m is on a rough horizontal surface and experiences a varying force F(t) from time 0 to t1, followed by only friction from t1 to t2. The block reaches a speed of v2 = 1 m/s at time t2, and the user is trying to determine t2, acceleration a2, and distance s2, while also needing to create a, v, and t diagrams. Initial calculations using impulse yielded a speed v1 of 4.346 m/s at t1, but the user encountered difficulties with integration and friction calculations, resulting in an unexpected t2 of 0.394 seconds. The user speculates that the actual t2 might be 1.808 seconds when accounting for earlier calculations.
Preach99
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Homework Statement


Hi guys. First of all, great forum you've got here.

I have a problem and I hope you can help me with this one.

Block of mass m lies on a rough horizontal surface. In the period 0 - t1, the block is moving due to the force F(t), which varies depending on the time. In period t1 - t2 we only have friction (F=0), and the block in the time t2 has speed v2=1 m/s. I have to find time t2, acceleration in t2 (a2) and distance s2. I also have to draw a, v, t diagrams.

Homework Equations



m2v⃗ -m1v⃗ 1=∫F(t)⃗ dt


The Attempt at a Solution



9q9w6b.jpg


my formula in mathcad

uvvx3.jpg


I'm stuck with this integration. I understand that the first part (F*cos(60°)) is the area under the curve - √2 *m*g

I hope you guys can help. Thank you in advance.
 
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wow, 400 views and no reply lol

I was quite busy today but I tried a different approach.
First, I only calculated the part from 0 to t1 with that Impulse formula and the speed v1 (@ t1) is 4.346 m/s.

Then, since the force is F=0, I have Fn=m*g (y axis), and Frx=-μ*m*g (x axis).
And when I try to calculate this part, I get a weird result -> t2=0.394 s lol.
IDK, this could only make sense if the real t2 time would be √2+0.394=1.808 seconds

:blushing:
 
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