I don't get the acceleration relation in this ex

AI Thread Summary
The discussion centers on understanding the relationship between the accelerations of two particles connected by a pulley system. The equations derived indicate that the tension in the rope and the forces acting on each mass are crucial to solving the problem. It is clarified that when one mass (m1) moves, the other mass (m2) moves twice as far due to the mechanics of the pulley, leading to the conclusion that m2's acceleration is also twice that of m1. The confusion arises from the interpretation of movement and acceleration, but the mechanics confirm that m2 indeed moves twice the distance of m1. This relationship is essential for solving the problem accurately.
Lenjaku
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Homework Statement


find the relationship between the 2 particles' accelerations.


Homework Equations


m1=20kg
m2=40kg
wheel doesn't weigh but can move.

both particles move with friction.

μs=μk=0.2

F(t)=98e0.1t

The Attempt at a Solution



I came up with 3 equations:
F(t)-fk1-T1=m1a1
T1=2T2
T2-fk2=m2a2

Why is the acceleration equation
a2=2a1?
 

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Lenjaku said:
Why is the acceleration equation
a2=2a1?

Due to the pulley.

If M1 moves 1 meter to the right how far does M2 move?

If M1 moves at a velocity of 1m/s to the right how fast does M2 move?

If M1 accelerates at 1m/s^2 to the right how fast does M2 accelerate?
 
The pulley is attached to m1. So they have to have the same acceleration when the rope between them is under tension. If the pulley moves 1 meter, then 1 meter of the m1 rope has moved on both sides of the pulley, so 2 meter of rope has gone past the pulley, so m2 moves twice as much as m1.
 
There is no mathematic explanation then? :( .Since the rope near the wall 'lengthens' the same value it 'shortens' near m2 while m1 keeps on going does it mean that m1 moves twice the distance m2 moves?If so it makes sense for me :S

edit:
I just noticed I mean m1 moves less than m2, m2 moves twice the distance >.<
 
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