Hi Jimmy,
That's correct for the most part, assuming the car's transmission and wheel bearings are perfectly frictionless. This actually isn't true in real life, so you can have a small amount of internal friction from the mechanics of the car itself, but no the road friction does not slow...
Hi bradsmith,
For part (a), because the 3 blocks are touching each other, they really just act like one mass, so the way you are splitting up the forces is not correct. Your formula should actually be F=(m1+m2+m3)*a. Make sense?
You would only have to use gravity in this type of problem if...
Hi dba80,
It sounds like you may be confusing yourself by trying to solve this problem all at once, when it would actually make sense to split this up into two separate stages:
(1) A projectile motion problem - forget about the sliding portion of the problem at first and just focus on this...
Hi Sam,
A couple of things:
(1) I think you're selling yourself wayyy short.
Is what you're saying to yourself here really true? How do you know your application won't stack up? Why wouldn't a great internship and being a Goldwater scholar stand out?
Regardless of what school you're...
Hi Jacobalg,
It would only be "bad" if you're not spending that time wisely.
From what I've found, the best use of your time in physics is:
(1) Deconstructing concepts (e.g. position, velocity, acceleration) into a simple form that you can personally understand. I recommend doing this by...
So first off, when I think of problems like these, I always always want to get my units in terms of radians, meters, and seconds. Start off by converting your units.
Second - what type of acceleration is this point experiencing? Is it speeding up or slowing down? Or is it staying at the same...
Hi LexRunner,
Yea it looks like you might be missing some info from your teacher.
What I would do is assign the velocity a variable called v0 to the initial velocity, and then solve the problem in terms of that. Then you can ask you teacher what that should be, and then plug in if needed...
You've got the formulas correct, but your answer to part (d) is not correct based on your initial drawing of the problem.
Go back and see if you can draw the at and ac vector components on your circle. Then compare the direction of at and v. Are they going in the same direction or different?
Ask yourself: what is escape velocity?
What are you "escaping" from and how might it be relevant to the Earth and Moon?
Your starting point, once you've answered those questions, should be a diagram of the Earth and Moon, showing some relevant forces.
Hi Ajay,
I would start by adding some additional detail to your sketch. Draw out each situation on an X-axis with some labels for your distance, and vector arrows labeled with the velocities va and vb.
Then work on creating the position equations for each car in each situation, as BvU...
Starting first with part (a), draw a vector showing the centripetal acceleration (ac) on your diagram. Ask yourself what centripetal acceleration is, and look up the formula.
Get this down first and you'll be able to solve part (a) and part (b).
Then worry about part (c) and (d) after you...
For anyone interested in quickly gaining a basic understanding of kinematics principles, here's a list of 15 top videos.
Enjoy!
1. Position, velocity, acceleration
2. Derivative graphs
3. Force
4. Mass and inertia 1
5. Mass and inertia 2
6. Mass and inertia 3
7. Newton’s...
For part (a) first find the rotational energy of the washer when it is rotating at w=240 rev/min. To do this first convert 240 rev/min to rad/second (by multiplying by 2*PI and dividing by 60). Then plug that number into KE = 1/2*I*w^2 along with I (which you already have as 1.2 kg*m^2). That's...