I am not following the template for the reason that this is a generic question.
Consider that the change in kinetic energy is 1J.
Suppose further you have two particles, both of equal mass that are gravitationally attracted to each other (and the change in energy comes from the fact that they...
Homework Statement
A monument is made from stone blocks of density 3800kg/m^3. The monument is 15.7m high, 64.8m wide at the base, and 3.6m thick from front th back. How much work was required to build the monument? (Hint: find ycm).
Homework Equations
ycm = (1/M) * ∫ydm, M = mass total...
Moments -- How are they actually calculated?
Hello, I have a question.
Is the moment calculated:
Force times the distance or
Force's perpendicular component (to axis) times the distance.
For example, lets say I have a stick.
Pulling on it is not moment.
So if I push at the...
Homework Statement
[EDIT] Cleaned up the problem.
A tread wheel crane is an ancient device used to lift heavy objects. It consists of a large circle (like a hamster wheel) for a person to walk inside. The large circle connects to the middle where there is a small circle that is attached a rope...
Homework Statement
A person standing at the top of a hemispherical rock of radius R kicks a ball (initially at rest on the top of the rock) to give it a horizontal velocity v.
What is the minimum initial speed to ensure the ball doesn't touch the rock?
Homework Equations
x^2 + y^2 = r^2...
This isn't a homework problem. I'm just having ALOT of trouble understanding how to do error propogation.
[EDIT] These are actually lab results. But its not a "homework" question. Its how to do uncertainty. Just trying to be clear.
Consider we take different measurements of an objects...
Homework Statement
Piano wire weighs 77kN/m^3 and breaks at a stress of 3000MPa. Calculate the length of piano wire that can be lowered down a very deep mine before it breaks.
Homework Equations
stress = force/area
The Attempt at a Solution
Piano wire = 77 000N/m^3
stress = 3000...
Lets say a sensor measures within accuracy of +/- 0.05N
And you take multiple measurements and graph it out. (I.e., 5.12N, 5.15N, 5.05N...).
What is the uncertainty of the final average?
One way I read is:
Sx = s/√N where s = std. dev.
N = number of data points
But...
A position of a particle in linear motion is given by:
x = vt + 0.5at2
Calculate x with the error for:
t = 25.3 ± 0.5s
v = 10.1 ± 0.4m/s
a = 2.5 ± 0.3m/s2
So for calculating vt:
q = (10.1) (25.3) = 255.53 (exact)
Δq = (10.1)(25.3) * √ (0.4/10.1)2 (0.5/25.3)2
= 11.31...
Therefore, vt =...
I have a problem.
Lets say there were two pulleys put at equal height.
You have a metal ring and attach three wires to it.
At the end of each wire, have three weights of mass w.
One weight hangs down, one weight goes over one pulley and the other over the other pulley.
The system goes to...
I have a question for which I am intensely confused.
Lets say a car was pushing a big truck from behind. And the car (and truck) are accelerating, then there is a breakdown because the car applies all the force it has to the truck, which pushes back with equal force. So the car shouldn't be...
Homework Statement
What is the electric potential two-fifths of the way through a parallel-plate apparatus (from the positive plate) if the plates have a total separation of 5cm and field strength of 5000N/C.
Homework Equations
Difference Potential Energy = Electric Field Strength x Distance...
This is probably a silly question.
The Electrical energy formula is this:
Ee = k(q1)(q2)/r
So lets say a positive and negative charge are directly next to each other.
Conceptually, there should be no potential energy there.
But the formula (r=0.00001m) suggests that it is huge.
On...
Hello and thanks! I apologize in advance if I picked the wrong place to post this thread.
I'm a high school student building a Rubens tube and have encountered a problem:
I have a one inch outside diameter aluminum tube.
It turns out that the one inch copper reducer and PTC I bought is...
Torque is the rotational force.
If there is more force, how can the motor be slow?
I'm building a DC motor and read that given a constant amount of coil, creating a very dense coil will increase torque but lower RPMs.
Conversely, making it looser (bigger radius) increases RPM but lowers torque.
Hello everyone!
I'm in high school and attempting to build a ruben's tube.
I am on a very strict budget and came across free brass tubing, but the diameter is 1 inch.
All the tutorials I've seen use a diameter of at least 2inches if not more.
Will a pipe with a one inch diameter work...
Hello and thank you!
I am having trouble understanding Mr. Thomas Young's equations for the double-slit apparatus with the bands etc.
Specifically, for constructive interference:
Length = PS1-PS2 = n(lamda)
What I understand is that this n value is the phase shift in their wavelength...
The Law: The direction of the induced current creates an induced magnetic field that opposes the motion of the inducing magnetic field.
Application: When the north pole of a magnet goes INTO a solenoid, the opening where the magnet is entering from becomes South. As it exits, the same opening...
I'm in grade 12 physics trying to understand how motors work. My teacher is useless.
I read the official law, but I do not understand how it conceptually works.
Here is the aplet he gave me, if you want to explain with respect to a visual...
Homework Statement
A 0.750kg block of wood is attatched to a spring with k = 300N/m. A 0.0030kg bullet is fired into the block, and the spring is compressed 0.102m.
Calculate the velocity of the bullet before the collision.
Is this elastic or inelastic?
Homework Equations
How do you do...
Homework Statement
A mattress manufacturer estimates that 20 springs are required to comfortable support a 100kg person. When supporting the person, the 20 springs are compressed 0.035m. Calculate the spring constant for one sprint.
Homework Equations
The answer is 1400N/M at the back of...
Hi, I'm new to this forum.
So I do not understand how, in an inelastic system, momentum is conserved.
Consider this problem:
Tarzan swings from a branch 4 meters up and picks up jane how far can he swing up the other side?
He weighs 100kg and is standing still on the branch. He jumps...