Answer: 12Mg/h
Explanation:
Let the spring is compressed by a distance x,before the lift stops,then
Mg(h+x)= 1/2 kx^2 ............... 1
Kx - Mg = M ( 5g ) ............ 2
Make x the subject in equation 2
Kx = 5Mg + Mg
Kx = 6Mg
x = 6Mg/k ............ 3
Put equation 3 into 1
Mg ( h + x ) = 1/2 kx^2
Mgh + Mgx = 1/2kx^2
Mgh + Mg × 6Mg/k = 1/2k × ( 6Mg/k )^2
Mgh + Mg× 6Mg/k = 1/2k 36M^2g^2/ k^2
h =18Mg/k - 6Mg/h
K = 12Mg/h
Answer:
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Explanation:
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Electron information needed to solve the question:
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![E=\frac{9.11x10{-31}kg*3.0x10^{12}m/s^2}{-1.6x10{-19}C}-[(19.0x10^3mj+18.0x10^3m)xi(400x10^{-6}T)]](https://tex.z-dn.net/?f=E%3D%5Cfrac%7B9.11x10%7B-31%7Dkg%2A3.0x10%5E%7B12%7Dm%2Fs%5E2%7D%7B-1.6x10%7B-19%7DC%7D-%5B%2819.0x10%5E3mj%2B18.0x10%5E3m%29xi%28400x10%5E%7B-6%7DT%29%5D)
![E=-i17.08N/C-[7.6(-k)+7.2(j)]N/C](https://tex.z-dn.net/?f=E%3D-i17.08N%2FC-%5B7.6%28-k%29%2B7.2%28j%29%5DN%2FC)
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Is the variable you change, independent, I, something I change.