Homework Statement
Which of the following phases is capable of permanently withstanding a force perpendicular to its surface?
A. Gas
B. Liquid
C. Solid
D. All of the above
Homework Equations
The Attempt at a Solution
I understand that the answer is D.
However, what does...
This may be a really silly, but do you assume the block will move down because there is no way it can move up or stay still? If the surface the woman was standing on included friction, would we then worry about if the block could would stay still or not?
Thank you very much! That was very helpful!
F(net) on the block
F = T - mg = m*a - mg = 50*a - 500
So now I don't know F(net) of the block, or its a. I'm tempted to say that it's -10, but that's acceleration due to gravity. I don't know T either, so I'm not sure where to go again. Am I completely overlooking something?
I know a is...
Or...since the surface is frictionless, the only force on the woman is in the horizontal direction.
If that force = 500 due to F(g), does she accelerate at a rate of 10 m/s^2?
Then tension would be 500N.
But what about the box?
So for the box, there are 2 forces acting:
Force of gravity = 50kg * (10) = 500N
Tension = 50 kg * a
How do I know what acceleration for tension is?
For the woman, I think there is only one force acting, which would be the tension of the rope.
T = 50kg * a
But setting the tensions equal at...
Homework Statement
A 50 kg woman dangles a 50 kg mass from the end of a rope. If she stands on a frictionless surface and hangs the mass over a cliff with a pulley as shown, the tension in the rope will be...
Homework Equations
F = m*a
The Attempt at a Solution
(no calculator...
So the electric field's work is all about not letting the proton accelerate while moving it?
I'm not sure if this is correct, but I'm picturing the proton naturally moving from the point of higher potential to the point of lower potential (requires no work from the electric field), and the...
One more question:
What does it mean that the work is negative? I looked up negative work, and the definition given was that it means the force is hindering movement, or that it is opposite to the displacement. I was confused, as I thought that a proton moving from higher potential to lower...
Homework Statement
How much work does the electric field do in moving a proton from a point with a potential of +260 V to a point where it is -48.0 V? Express your answer in electron volts.Homework Equations
V = p(A) - p(B)
The Attempt at a Solution
V= 260 [v] - (-48.0[V]) = 3.08×102 [V]...
Oh, I added the two final numbers together:
3.78x10^7 + 5.037x10^7 = 8.82x10^7
and got the right answer. But I don't understand - why would you add the negative charge?
Homework Statement
What is the electric field at a point midway between a -8.50μC and a +6.38μC charge 7.79 cm apart? Take the direction towards the positive charge to be positive. Assume no other charges are nearby.
Homework Equations
E(net) = E(1) + E(2)
E = (k*q)/r^2
The...
I think what you all are saying is that this height is indeed significant (please ignore if that's not what you actually intended to convey!), which is what I thought when I was first trying to solve this problem:
A student decides to throw a rock off a cliff. The rock leaves the top of the...
Ah!
Oh! so since we're talking about displacement, only the starting and ending positions of the particle matter? It doesn't matter where the particle goes in between 310 m and 0 m.
Thank you! (unless I got this wrong...again!)
In projectile motion problems, where an object is thrown (not horizontally) off of a cliff, does only the cliff's height matter to this equation:
y = v_y * (t) + (a * t^2)/2
What I'm confused about is the little bit of height gained by the object when it is first thrown off of the cliff...