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Physics problem please help! Work/Forces?
A 12 kg runaway grocery cart runs into a spring with spring constant 240 N/m and compresses it by 80 cm.
What was the speed of the cart just before it hit the spring?
2 Answers
- 1 decade agoFavorite Answer
Using energy conservation
See right away it is compressed .8 meters after converting
KE = PE of spring (this formula can be derived using integrals, your teacher probably gave you it)
1/2mv^2 = 1/2kx^2
If we solve for v...
v = sqrt[kx^2)/(m)]
v= sqrt[(240N/m*.8m^2)/(12kg) = (8sqrt(5) / 5) *exact* = 3.6 m/s after rounding
- ?Lv 45 years ago
Draw a drive diagram. (It's continually excellent to attract a diagram you probably have angles to remember.) two hundred cos(70) = horizontal aspect of the drive. You appear to have a misprint: the paintings performed within the horizontal path is that this drive occasions the space of five meters (however you used three m for your final line??) So the paintings performed is (two hundred)(five)cos(70) joules And, sure, you have been running in opposition to friction. You honestly did paintings within the vertical path while you lifted one finish of it, however the web paintings within the vertical path is 0, given that you accurately placed that finish down once more.