Hi All,
Consider a situation in which a coaxial cable have electric current i(t) = Imax * cos(w*t) flowing through its cilindrical inner cylindrical core (with radius a) and the inverse current flowing on its surface cover (with radius b).
I would like to know if it is correct to say that...
A clock has a 20cm minute hand. From the 6PM mark to the 9PM mark, for the tip of the minute hand, calculate:
a) the displacement vector in unit-vector notation
b) the average velocity vector in unit-vector notation
c) the average acceleration vector in unit-vector notation
d) calculate...
Homework Statement
Suppose the field inside a large piece of dielectric is \vec{E}_{0}, so that the electric displacement is \vec{D}_{0}=\epsilon_{0}\vec{E}+\vec{P}.
a. Now a small spherical cavity is hollowed out of the material. Find the field at the center of the cavity in terms of...
Here is my question.
The function v(t)=15\cos{3t}, 0 \leq t \leq 2 \pi, is the velocity in m/sec of a particle moving along the x-axis. Complete parts (a) through (c).
a.Graph the velocity function over the given interval. then determine when the motion is in the positive direction and when...
I having a bit of trouble understanding Joos's treatment of virtual displacements. I am referring to pages 114 and 115 of Theoretical Physics, By Georg Joos, Ira M. Freeman
http://books.google.com/books?id=vIw5m2XuvpIC&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false...
Dear all,
Can anyone explain the the phase lag between force and displacement in single degree of freedom forced vibration with viscosity damping?
The response of phase angle derived by mechanical vibration as below ( assuming force is excited harmonically) :
Phi(ω) = arctan( C*ω / ( K...
Homework Statement
A grasshopper jumps 1.00 meters from rest, with an initial velocity at a 45.0° angle with respect to the horizontal. Find (a) the initial speed of the grasshopper and (b) the maximum height reached.Homework Equations
vx = v0xt = v0cos θ0
vy = v0 sin θ0 - gtThe Attempt at a...
A golfer lines up for her first putt at a hole that is 13 m exactly northwest of her ball’s location. She hits the ball 13 m and straight, but at the wrong angle, 39° from due north.
a) In order for the golfer to have a “two putt green,” determine the angle of the second putt...
Homework Statement
Find the potential energy function for a spring if the origin is placed at the wall and the unstretched length of the spring is L. Show that with a suitable choice of the constant, this potential function is proportional to the square of the amount that the spring is...
I was looking for some help on getting displacement from acceleration data (using an accelerometer). I found this old PF thread - https://www.physicsforums.com/archive/index.php/t-123128.html
I am familiar with the double integration/trapezoidal integration. It isn't much help.
The FFT method...
1. v=s/t where s represents the displacement
2. s=rθ where s represents the arc length
v=rθ /t
Why can substitute here?
I guess that is not same things.
An arc length is not a straight line but displacement is which is shortest distance between initial and final point.
Homework Statement
A ball is thrown vertically upward from a window at 10m/s. It hits the ground 5.0 seconds later. What is the height of the window from the ground?
Given
Vi = 10 m/s
Vf = 0
Δt = 5.0 m/s
Δa = -9.8 m/s^2
Find
Δd(w-g) = ?Homework Equations
Δd = Vi(Δt) + Δa(Δt)^2
And the...
Hi,
in this setup we have a bucket of water 10 kgs of water inside. Attached is a weight meter measuring that in fig a. The weight is exactly 10kgs.
In fig b. A piston (red) is being pulled by a weight (z).
"z" has a pull force equivalent to the volume of the column of water above the piston...
Hello-
I am trying to find a reference describing the z(or c) component of the basis vectors for graphene. I seem to recall that there is a slight bend such that half of the atoms lie slightly above the plane. However, every paper I have found references the perfect 2D lattice of Graphene...
Homework Statement
From Tipler & Mosca, Ch. 2, #56 (pg. 57)
Bats use echo location to place themselves. (I condensed all of this from the problem) So:
Bat flying at 19.5 m/s toward a vertical cliff.
Bat clicks.
Bat hears the echo 0.15 s later. (click travels at 343 m/s)
How close is the bat...
Homework Statement
A car moves east at 18 m/s for 5 minutes. What its displacement? It says that the answer
to this question from my teacher is: 5400 m.
Homework Equations
→ →
X= v *t
The Attempt at a Solution
→
V= 18 m/s [E]
t= 5 min.
→ → →
X= v *t =...
Homework Statement
I do not know if this is the correct forum to post this in but here goes. I got all of the answers correct, but I just have a question on part F.
1.) The figure shows a motion diagram
of a particle in circular motion at a
constant speed. The axes have units
of...
As you walk to class with a constant speed of 1.65 m/s , you are moving in a direction that is 16.2° north of east.
How much time does it take to change your displacement by 25.0 m east?
I know that v0 = 1.65 m/s. Would I use the equation: x = (v0 cosθ)t?Any help or advice would be much...
Homework Statement
Homework Equations
Above
The Attempt at a Solution
Okay, so I understand I need to integrate the top equation because it's velocity as a function of time.
I just don't know how.
Hey everyone. I'm sort of new to the whole physics world (I'm doing it in highschol currently).
I have one question that I apparently can't figure out.
An object accelerates uniformly from rest. After 7.50s, the velocity is 53.2m/s north. What is the displacement?
I first did d=tv and got...
1. Are these two the same? I'm not sure. Sometimes my teacher labels the Y axis with a Delta Displacement [E]. Other times it's just Position (M), so I'm not sure how to identify if we are finding Speed or Velocity.
I'm just assuming they are the same.
2. Also, position is a Vector quantity...
Homework Statement
A pulley fixed to a rigid support carries a rope whose one end is tied to a ladder with a man and the other end to a counterweight of mass M. The man of mass m climbs up a distance h with respect to the ladder and then stops. If the mass of the rope and the friction in the...
In a hypothetical situation, including every type of hypothetical situations, can a displacement be greater than, less than, or equal to the total distance?
Homework Statement
A car travels in a straight line at 40 km/hr for 1 h and 60 km/hr for 2 h. A) How far does it travel? B) Find the average velocity.
Homework Equations
Average velocity = Δx/Δt (change in distance/change in time)
The Attempt at a Solution
In solving for A, I...
Homework Statement
The displacement vectors A and B, when added together, give the resultant vector R, so that R= A+B . Use the data in the drawing and the fact that = 29° to find the magnitude R of the resultant vector and the angle θ that it makes with the +x axis.
I am unsure how to...
Homework Statement
A harmonic oscillator has angular frequency ω and amplitude A. What is the magnitude of the displacement when the elastic potential energy is equal to the kinetic energy? (Assume that U = 0 at equilibrium.)
Express your answer in terms of the variables ω and A...
A watermelon seed has the following coordinates: x = -6.6 m, y = 2.2 m, and z = 0 m. Find its position vector as (a) a magnitude and (b) an angle relative to the positive direction of the x axis. If the seed is moved to the xyz coordinates (8.2 m, 0 m, 0 m), what is its displacement as (c) a...
Hi everyone,
I am taking a physics course this year and I find myself already looking for help unfortunately. I think I understand the basics of adding vectors using Ax = A cosθ , Ay = A sinθ, etc. I am getting confused with the 3rd leg of the trip though. Since it is due west wouldn't that...
Wein's displacement law is
E (T,ν) = = v3F (v/T)
This is from Omnes' book on QM
He doesn't explain why the total radiation is infinite. I'd like to know why.
Hi,
Could someone explain how the following two definitions of the displacement operator are equal? The first is the standard one
1) e^{\alpha a^{\dagger}-\alpha*a}
But what about this one? This is from a Fock state decomposition of a coherent state.
2) e^{\frac{-|\alpha^{2}|}{2}}e^{\alpha...
The question is:
A 56.0 kg bungy-jumper hangs suspended from her bungy-cord, at rest. She is displaced from this position by 15.0 m downward, and then released. She bounces up and down, with a period of 5.800 s. Assume the woman undergoes simple harmonic motion, described by
y(t) = X cos(2...
Homework Statement
A child rides on a pony around a circular track with a radius of 4.5 meters.
Homework Equations
What is her distance traveled and displacement after she has gone half way around the track?
The Attempt at a Solution
If this the wrong section to post this, please know that I am very sorry, but I don't know much about any of the things going on, on here so please bare with me.
Say you got some powder, and say this powder has a density of 1.06g/cm3 (or 1.06g/mL, right?).
Now say you want to put 2500mg...
Hi. I was just wondering if gases displace each other. For example, if I set up an apparatus to produce oxygen gas like the one shown in this diagram
would the oxygen produced in the flask displace the air that is already present in the apparatus? Or would the oxygen gas and air simply "mix"?
A car us driven at a velocity of 72km/h EAST for 0.50hr, 48km/h NORTH for 0.25hr, and 62km/h WEST for 0.50hr. Calculate the magnitude of its displacement.
Attempt at the solution:
Distance = Speed * Time
(72 x 0.5) + (48 x 0.25) - (62 x 0.5) = 17km
However, the answer in the book...
I'm working on a Java project to simulate Newton's Cannon (example: http://spaceplace.nasa.gov/how-orbits-work/).
How do I find the x and y components of displacement, velocity and acceleration of the projectile after a time Δt?
I know that I need to use Newton's law of gravitation, however I...
OK, I was thinking about transformers and mutual induction and then drifted onto displacement current. I then decided to build a simple test apparatus and test for the magnetic field between two parallel plates. using a variety of coil designs to have as much of the windings perpendicular to the...
http://community.accelrys.com/servlet/JiveServlet/showImage/2-14223-12512/%E5%9B%BE%E7%89%871.png
I want to assign displacement to the top edge of the above model in Material Studio. How to realize it ? Thank you !
Homework Statement
A catapult (slingshot) is used to fire a ball of mass 0.2kg vertically into the air. The elastic is stretched so that there is a tension of 40N in both 'sides' of the slingshot, ie on the elastic on either side of the mass (I am trying to describe a diagram here, so...
Velocity, displacement and position time graph help!
cyclist road east for 1.0x10^2 m with a constant velocity of 25 m/s she then accelerates down a hill and 5s later reached the bottom of the hill with a velocity of 50m/s
a) how long did the cyclist ride before reaching the hill?
B)what is...
Is it valid to subtract a position vector of direction E with one of direction W or do they both have to have the same dierction when using the net displacement formula?
Homework Statement
A small body is undergoing simple harmonic motion on a frictionless horizontal surface with an amplitude of 0.13m. At a point 0.05 m from equilibrium the velocity is 0.24 m/s. a.) what is the period?
What is the displacement and acceleration when the velocity is ±0.10 m/s...
Homework Statement
How would you find the displacement of a velocity/time graph when it is in the shape of a parabola?
Homework Equations
I know Velocity x time = displacement.
The Attempt at a Solution
I know that velocity x time = displacement, but how do you find the area under...
Homework Statement
A clock is showing 3.30. Calculate the angular displacement in degrees from the 12.00 position of the clock to:
i the minute hand
ii the hour hand
I got my minute answer as 180 degree, which is right. But my second answer was 90 degrees, which apparently is wrong! the...
Homework Statement
After three days of hiking, a group of hikers are 30km N from their starting position. On the first day, they hiked 20km E. On the second day, they hiked 30km 53 degrees N of W, calculate their displacement on the third day.
Homework Equations
I haven't a single clue...
Homework Statement
You walk to the corner store after school to buy a carton of milk before going home. The store is 750 m south of the schoo, and your house is 625 m north of the school. What is your net displacement.
Homework Equations
dT=d1+d2
formula for displacement
The...
Homework Statement
Using method of virtual displacement get the stress tensor for this problem.
http://img32.imageshack.us/img32/7272/problemba.png
The attempt at a solution
The given system is 4-times tatically indeterminate. Since it is symetrical we can split it in half vertically...
Hi everyone!
Anyone knows what is the maximum displacement covered by a body in a time equal to half of its time period? Please also give an example. Thank you.
Homework Statement
An object starts at rest and accelerates at 2.5 m/s^2 for 12 seconds. It then moves at a constant velocity for 5.0 seconds and then slows down uniformly at 1.5 m/s^2 until it stops. Calculate:
a) the constant velocity
b) the time taken for deceleration
c) the total...