(adsbygoogle = window.adsbygoogle || []).push({}); Simple problems that I cant figure out!!! HELP!!

Hello, first of all, thanks in advance for checking out my thread. below are a short list of some simple problems that should be easy to solve for those of you who frequent this forum. However, I cant seem to figure them out and it is really getting on my nerves. If you have any ideas, i would really appreciate your help. Included with the questions are the numerical answers. As such, I am solely interested in the steps and formulas required for them. THANKS!

Q) A hockey stick gives a hockey puck an initial velocity of 12m/s. If the coefficient of kinetic friction is 0.2, how far will the puck travel before stopping? (ANS = 36m)

Q) A uniform 25 kg board is 12m long and has a 50kg weight attached to one end. How far from the weight will be the center of gravity of this system? (ANS = 2)

Q) A block of mass 4 kg rests on a horizontal surface. The coefficient of sliding kinetic friction between the two is 0.2. A string attached to the block is pulled horizontally by a force with an acceleration of 3m/s2. What is the magnitude of this force? (ANS = 20N)

Q) A CD and spindal together have a moment of inertia of 2x10-4kgm2. They rotate with an angular velocity of 4 rad/sec. What is the net torque that must be applied to bring the system to rest within 2 s? (ANS = 4x10-4 Nm)

Q) A 2.0m wire segment carrying current of 0.5A is oriented at an angle of 30o to a uniform magnetic field of 0.5T. What is the magnetic force of the wire? (cos30 = 0.87, sin30 = 0.5) (ANS = 0.5N)

Q) Given the quantum mechanical model of the hydrogen atom, if the orbital quantum number is 4, then how many diff orbital magnetic quantum numbers are permitted? (ANS = 9)

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# Homework Help: Simple problems that I cant figure out HELP

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