- #1
teme92
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Homework Statement
(a) A block of mass m = 2.00 kg sits on a massless platform supported by a vertical
spring with spring constant k = 55.0 N/m. How much is the spring compressed?
(b) The block is now lifted off the platform and dropped from a height h = 1.5 m
above the platform and spring. What is the speed of the block just as it reaches
the spring?
(c) What is the maximum compression of the spring by the block?
(d) Just as the block leaves the spring moving upward, another identical block is
dropped from a height h2 = 2.5 m above the equilibrium position of the spring.
How far above the spring are the two blocks when they collide?
Homework Equations
F=ma
F=-kx
v2=u2 + 2as
KE=0.5mv2
PE=0.5kx2
W=0.5kd2
The Attempt at a Solution
(a)
I used ma=-kx and got 2(-9.8)=-55x →x=0.356m
(b)
Using v2=u2 + 2as, where s=-1.5, u=0, a=-9.8
I got v=5.422ms-1
(c)
I used W=KE + PE
And got d = 1.0935m
(d)
It is here where I have trouble. Could anyone tell me if I have used the right methods up til now? I get for part (d) I'm trying to find when both masses have equal h values but I don't know how to show that.