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nysnacc
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Homework Statement
Homework Equations
f = mu_k * N
F=ma
gneill said:It looks like your method for finding the net force acting along the slope is okay. But you may want to recalculate the friction force; The result doesn't match what I think it should be. Perhaps a calculator slip? I see that you've made one of the angles 30° in your work, but that's probably just a typo, right?
Once you've found the acceleration you shouldn't need to integrate if you know your basic kinematic formulas.
You've been finding the components of the various forces along the x and y directions using the trig functions. So you already have them in hand. The friction force is directed along the slope, for example.nysnacc said:What is the formula for the sum of force in x -direction (my x coordinate is not horizontal) ??
If you have the net force acting on mass M along the direction of the slope, what's the acceleration of M in that direction? Knowing acceleration the rest is basic kinematics.nysnacc said:Cuz, I need to find v, what will be a better way if not integrating acceleration?
That's right, assuming you mean the components of F and g force that are directed along the slope. It's the net force that causes the mass to accelerate. Note that it's entirely possible that F will be insufficiently large to prevent the mass from sliding downslope rather that upslope! You should check the magnitudes of the upslope F component against the downslope g component prior to "adding" you friction. Friction always opposes the direction of motion.nysnacc said:I mean: net force = force applied - weight - friction,
then divide m to get a
Yes, I meant the net force in x dir.gneill said:That's right, assuming you mean the components of F and g force that are directed along the slope. It's the net force that causes the mass to accelerate. Note that it's entirely possible that F will be insufficiently large to prevent the mass from sliding downslope rather that upslope! You should check the magnitudes of the upslope F component against the downslope g component prior to "adding" you friction. Friction always opposes the direction of motion.
If the box slides downslope then the friction will oppose that motion. There's only ever one friction force operating between surfaces and it always opposes the motion that is taking place (or, in the case of static friction, trying to take place).nysnacc said:Yes, I meant the net force in x dir.
As we push the box, up the slope, there is a friction opposing, but the force applied is not strong enough, so the box slide down. Is there a friction (in -x direction) opposing the motion?
Then I can divide mass to get a..gneill said:That looks good.
Sure, but it's easier to apply standard kinematics equations. Remember SUVAT?nysnacc said:Then I can divide mass to get a..
and then integrate a = get v?
Nope, Like a= vr +vθ thingy?gneill said:Sure, but it's easier to apply standard kinematics equations. Remember SUVAT?
Ah. The flash of insight!nysnacc said:OHH v=u+at
Inclined plane motion is the movement of an object along an inclined surface, such as a ramp or a hill. It occurs when a force is applied to an object at an angle to the surface it is on.
The angle of inclination, or the angle at which the inclined plane is tilted, affects the force required to move an object up or down the plane. The steeper the angle, the greater the force needed to overcome gravity.
The longer the inclined plane, the less force is needed to move an object along it. This is because the longer the plane, the more it spreads out the force needed to overcome gravity.
The equation for calculating the force required to move an object on an inclined plane is F = mgsinθ, where F is the force, m is the mass of the object, g is the acceleration due to gravity, and θ is the angle of inclination.
Friction acts in the opposite direction of motion on an inclined plane, making it more difficult to move an object. The greater the friction, the more force is needed to overcome it and move the object.