Recent content by suxatphysix

Thank you, I got (f) right. But for (b) I have another question. For the quadratic equation does c = 0? To decide which one is right, you pick the positive one because time cannot be negative. For my answer I am getting 0. This doesn't sound right.

Homework Statement The position of a particle moving along the x-axis depends on the time according to the equation x = ct2 - bt3, where x is in meters and t in seconds. For the following, let the numerical values of c and b be 3.5 and 1.0 respectively. (b) At what time does the...

i got both b and c. b - 36.69 c - 43.85 thanks learningphysics for getting me started on that problem. Much appreciation.

omg it was right! thanks! now to try and answer part b and c.

\Deltat=-vi +/- \sqrt{vi^{2}+2ay} / a

why 9.81 when gravity is always negative?that means the time would actually be 0.723? i don't know if that sounds logical

vf^{2}=0 + 2(-9.8m/s^2)(-68.6m) vf= 36.69m/s \Deltat = -36.69m/s +/-\sqrt{36.69m/s^2 + 2(-9.8m/s^2)(-29.4) } /-9.81 =8.20s

got 8.20 for part a seconds but it was wrong. so i stopped at part a

Homework Statement A bolt is dropped from a bridge under construction, falling 98 m to the valley below the bridge. (a) In how much time does it pass through the last 30% of its fall? (b) What is its speed when it begins that last 30% of its fall? (c) What is its speed when it...

ty got it right

thanks, got part a right. for b, I'm getting 42.18. is that right and would it be negative if it is going down? used vf= vi + a*t and vf^2=vi^2+2*a*d

Homework Statement A hot-air balloon is ascending at the rate of 13 m/s and is 90 m above the ground when a package is dropped over the side. (a) How long does the package take to reach the ground? (b) With what speed does it hit the ground? Homework Equations The...

got it. Ftrailer = 2150kg(-9.8m/s^2) Ftrailer = 21,070N Fresultant = FJeep + Ftrailer Fresultant = 21,000N -21070N Rresultant = -70N -F=ma -70 N = (850kg + 2150kg)a a=0.023 m/s^2

Homework Statement In the movie "Jurassic Park 2", a jeep is struggling to pull a trailer back up from over a cliff. The jeep is connected to the trailer by a cable. The jeep in on level ground and the trailer hangs from the cable over the of the cliff. The jeep has a mass of 850 kg and pulls...

cool thanks, got the answer