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kevinr
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[SOLVED] Simple Harmonics Question
A 1.40 kg ball and a 2.20 kg ball are glued together with the lighter one below the heavier one. The upper ball is attached to a vertical ideal spring of force constant 170 N/m, and the system is vibrating vertically with amplitude 19.0 cm. The glue connecting the balls is old and weak, and it suddenly comes loose when the balls are at the lowest position in their motion.
m1 = 1.4 kg
m2 = 2.2 kg
k = 170 (not sure)
(1/2)kx^2
(1/2)mv^2
(m1+ m2)v(both) = mv.
Ok so i got the frequency of this problem to be 1.4 and that's correct. But I am lost in finding the amplitude.
Here's what i have done but its wrong. (I think since mass is less - amplitude should be less)
i want to use conservation of momentum (m(both)v(both) = mv) to find v of m2 so i first need v of both.
For that i need v(both) so i used conservation of energy (1/2kx^2 = 1/2mv^2) -> which gives me v(both)
With that i use to find v of m2 using m2v2 = m(both)v(both). Now with the v of m2, i use energy conservation again (1/2kx^2 = 1/2mv^2) to find x for just m2. This should be the amplitude but the answer seems to be wrong) - i get 17 cm.
Is my approach ok? Any help would be great.
Thanks!
Homework Statement
A 1.40 kg ball and a 2.20 kg ball are glued together with the lighter one below the heavier one. The upper ball is attached to a vertical ideal spring of force constant 170 N/m, and the system is vibrating vertically with amplitude 19.0 cm. The glue connecting the balls is old and weak, and it suddenly comes loose when the balls are at the lowest position in their motion.
m1 = 1.4 kg
m2 = 2.2 kg
k = 170 (not sure)
Homework Equations
(1/2)kx^2
(1/2)mv^2
(m1+ m2)v(both) = mv.
The Attempt at a Solution
Ok so i got the frequency of this problem to be 1.4 and that's correct. But I am lost in finding the amplitude.
Here's what i have done but its wrong. (I think since mass is less - amplitude should be less)
i want to use conservation of momentum (m(both)v(both) = mv) to find v of m2 so i first need v of both.
For that i need v(both) so i used conservation of energy (1/2kx^2 = 1/2mv^2) -> which gives me v(both)
With that i use to find v of m2 using m2v2 = m(both)v(both). Now with the v of m2, i use energy conservation again (1/2kx^2 = 1/2mv^2) to find x for just m2. This should be the amplitude but the answer seems to be wrong) - i get 17 cm.
Is my approach ok? Any help would be great.
Thanks!