|Register||Search||Today's Posts||Mark Forums Read|
|Physics Forum Physics Forum. Discuss and ask physics questions, kinematics and other physics problems.|
| ||LinkBack||Thread Tools||Display Modes|
I have no clue about this PROBLEM!!!?
Can anyone give me detailed description of how to this and what formula to use?
Thank you so much for the help!
A block with mass m = 15.6 kg slides down an inclined plane of slope angle 14.7o with a constant velocity. It is then projected up the same plane with an initial speed 2.80 m/s. How far up the incline will the block move before coming to rest?
The missing piece is the frictional force of the block against the plane. The first part of the problem lets you find that value:
If the block moves at constant velocity, the friction force Fr is equal to the force (gravity) pulling the block down. The gravity force on the block is m*g*sin?; therefore Fr = m*g*sin?.
You can solve the second part in two ways: energy conservation or mechanics. I prefer energy conservation:
Initial energy of the block = KE = 0.5*m*v0². The block will rise on the plane until that energy is used by friction and gravitation potential energy.
Friction energy used is Fr*L, where L is the distance along the plane
Gravity potential = m*g*h, where h is the altitude at the end of travel. If L is the distance traveled, h = L*sin?. So the total energy used going up the plane is
Fr*L + m*g*L*sin? and this is equal to 0.5*m*v0². Then using Fr from the first part,
m*g*L*sin? + m*g*L*sin? = 0.5*m*v0²
g*L*sin? + g*L*sin? = 0.5*v0²
L*2*g*sin? = 0.5*v0²
L = 0.25*v0²/(g*sin?)
|clue , problem , _|
|Thread||Thread Starter||Forum||Replies||Last Post|
|2D PAGE problem||antheab||Peptide Forum||3||12-26-2010 03:28 PM|
|SDS-PAGE problem||Steve Nothwehr||Protocols and Methods Forum||2||10-16-2009 08:59 AM|
|weird problem in transfecting 293 cells in 24-well plate||ÕÔÇï»Ô||Cell Biology and Cell Culture||1||04-17-2007 03:54 AM|
|N-body problem||Torstein Raanes||Physics Forum||1||12-01-2003 09:31 AM|
|Integration Problem / Finding Contour lines Problemfirstname.lastname@example.org||Physics Forum||2||09-07-2003 11:28 PM|