Net Definition and 1000 Threads

similar to the rough picture of how BHs radiate if I put a proton next to a BH can one of the quarks be absorbed into the BH and the other two escape? I don't really understand confinement very well but does the confinement picture change next to BH horizon?

Homework Statement Homework Equations Net Torque = F1I1 + F2I2The Attempt at a Solution In the y direction, the net force is: 0 = F2-Fg, so F2=Fg. I attempted to do the problem by resolving the net torque, where I defined CW as positive and CCW as negative, so I got: Net Torque = (0.750m)F1...

Homework Statement A 9.0 uF and 4.0 uF capacitors are connected in parallel, and this combination is connected in series with a 12.0 uF capacitor. a) what is the net capacitance? b) if 32 V is applied across the whole network, calculate the voltage across each capacitor. Homework...

does anyone know why momentum is not conserved in this problem? I thought momentum was always conserved when no net force acted on the system? Is the ground considered the net force acting on the system? Even though it changes direction I was thinking momentum would still be conserved except...

I have been trying to derive a formula for the forces acting on and the centre of gravity of objects in a one dimensional space. I've started in one dimension to make things easier and intend to move on to two dimensions soon. I tried to do it without referring to any source and I got a solution...

Homework Statement A man is pushing a 75 kg crate at constant velocity a distance of 12 m across a warehouse. He is pushing with a force of 225 N at an angle of 15° down from the horizontal. The coefficient of friction between the crate and the floor is 0.24. How much work did the man do...

Homework Statement A square loop of wire of side length L lies in the xy-plane, with its center at the origin and its sides parallel to the x- and y- axes. It carries a current i, in a counterclockwise direction, as viewed looking down the z-axis from the positive direction. The loop is in...

Homework Statement What is the force F on the 1 nC charge at the bottom? Figure: http://session.masteringphysics.com/problemAsset/1384340/5/pic1.jpg Homework Equations Coulomb's law - k*qq/r^2 The Attempt at a Solution 1) After splitting up the net force into their respective...

Homework Statement Calculate the net force acting on each object indicated in the following diagrams. (diagrams attached) Homework Equations Sine Law: sin a/a = sin b/b = sin c/ c Cosine Law: c^2 = a^2 + b^2 -2ab*cos(c) SOHCAHTOA The Attempt at a Solution a) c2 = a2 + b2 –...

I decided to explore microsoft softwares but didn't quite get it. What is .NET and visual studio? Is it a framework to make things easier to develop or is it something more? I till now have made C/C++ programs using vim and gcc on my ubuntu. For web I used web2py. Is .NET something like...

Homework Statement Two crewmen pull a raft through a lock. One crewman pulls with a force of 130N Southwest at an angle of 34 degrees below the horizontal. The second crewman pulls at an angle of 45 degrees above the horizontal Northwest. With what force should the second crewman pull so that...

Homework Statement The drawing shows three point charges fixed in place. The charge at the coordinate origin has a? q1 = +8.50 µC; the other two have identical magnitudes, but opposite signs: q2 = -5.00 µC and q3 = +5.00 µC. http://img66.imageshack.us/my.php?image=p1818mv9.gif (a)...

Homework Statement A ball on a porch rolls 60 cm to the porch's edge, drops 40 cm, continues rolling on the grass, and eventually stops 80 cm from the porch's edge. What is the magnitude of the ball's net displacement, in centimeters? ball starts rolling here \/ rolls 60cm-> #----------#...

Homework Statement A ball on a porch rolls 60 cm to the porch's edge, drops 40 cm, continues rolling on the grass, and eventually stops 80 cm from the porch's edge. What is the magnitude of the ball's net displacement, in centimeters? Homework Equations d = a^2 + b^2 The Attempt at a...

Homework Statement A long hollow nonconducting cylinder (radius R= 0.060 m, length L= 0.70 m) carries a uniform charge per unit area of σ= 4.0 C/m^2 on its surface. Beginning from rest, an externally applied torque causes the cylinder to rotate at constant acceleration α= 40 rad/s^2 about the...

Homework Statement Consider the following ring: Considering that \theta = 30°, determine F1 and F2 in order for the net force to be oriented downards with magnitude 10^3 N and without any horizontal component. The Attempt at a Solution Alright, so, the problem is I find two conflicting...

Homework Statement The charge distribution in the figure to the right is a cylindrical solid of charge q, radius R, and length H. The Gaussian surface S is a cylindrical shell with radius r and length h, with r > R. Determine the net electric flux given that q = 12Q, R = 5L, H = 6L, r does not...

Quick question about net external work Got a block (A) attach to Spring which attach to a Wall Hand pushes A toward the wall which compress the Spring So hand is doing positive work on A, W = F*D, work is whatever force by hand times distance.. But work done ON the spring BY the wall is...

Hi I have a ball, and I'm lifting this ball upward with +work, and gravity is doing -work, Net Work= zero. But how is it, that I can still move the ball. When read that explanation I think of the ball or any object not moving at all :S So how can I figure this puzzle out :O?

Homework Statement I am trying to derive an equation for the net force, or thrust, acting upon a rocket. The equation I get is different from the standard equation given in most textbooks, so I want to know where I am going wrong.Homework Equations F = d(mv)/dt I also make use of the...

In the figure, a square of edge length 16.0 cm is formed by four spheres of masses m1 = 4.50 g, m2 = 2.80 g, m3 = 0.800 g, and m4 = 4.50 g. In unit-vector notation, what is the net gravitational force from them on a central sphere with mass m5 = 2.10 g? F = G (m1m2/r2) To get the...

Homework Statement While someone is accelerating upwards but before the body leaves its feet, is there a net force? The person will eventually leave the ground. Homework Equations ƩFy = 0; or does ƩFy = ma? The Attempt at a Solution I pretty sure that the latter is true, this is so...

Hello all, I am so confused on why a net torque on a dipole in a uniform electric field would not be equal to zero. Wouldn't one end rotate clockwise, the other counterclockwise and cancel out to zero? Thanks.

Does a criss-cross resistor network exist? I need something (preferably passive), that comes in both criss cross and straight paths. Maybe a switching array of some sort? I am looking for something that connects- A-->A B-->B C-->C D-->D and A-->D B-->C C-->B D-->A It can be...

Homework Statement Two point charges Q1 = -58.6 mC and Q2 = +35.4 mC are located so that Q1 is directly above Q2. The coordinates of Q1 is (-12.0 cm, +15.6 cm). The two charges are 42.8 cm apart. Determine the coordinates of the location where the net electric field due to Q1 and Q2 is zero...

Homework Statement Ascending a 1 in 10 hill, a 1500 kg car slows down from 100 km/h to 50 km/h in a distance of 400 m. Calculate the net tractive force F between the tyres and the road assuming F remains constant and wind resistance can be neglected. Is the driver braking during this period...

Suppose we have a hollow spherical shell made of a conducting metal, inside a slightly larger hollow spherical shell made of the same conducting metal. The shells are separated by a layer of insulation, so that the assembly is basically a spherical, hollow capacitor. If I cause the inner shell...

A box of mass 5.0-kg is accelerated from rest across a floor at a rate of 2.0m/s^2 for 7.0s. Find the net work done on the box? W=Fd

Homework Statement A girl pulls her 4.00kg sled connected to a weightless rope. She pulls the rope on the sled and it goes faster and faster on a frictionless ice surface. The sled has an acceleration of 2.50m/s^2. What is the tension on the rope? What is the net force? Homework...

Homework Statement First, let us consider a sled of mass m being pulled by a constant, horizontal force of magnitude F along a rough, horizontal surface. The sled is speeding up. Let us now consider the situation quantitatively. Let the mass of the sled be m and the magnitude of the net...

Three rescuers are pulling horizontally on a safety net to keep it taut. One pulls northward with a force of 295n; the second pulls in a direction 31 degrees south of west wit ha force of 250N. In which direction and with what force must the third pull to keep the net stationary? I don't know...

Homework Statement 75.0kg Man decends from 3.1m above the ground. At 3.1m his feet touch the ground and he absorbs the landing through a constant acceleration of 0.6m to come to a verticle rest. What is the net force on him? Homework Equations Vi = √(2*a*y); a = -[(Vi)^2]/(-2*y); F =...

Homework Statement a cylindrical solid of charge q, radius R, and length H. The Gaussian surface S is a cylindrical shell of radius r and length h, with r < R. Determine the net electric flux given that q = -48Q, R = 4L, H = 3L, r = 2L, and h = 2L (type the integer value, along with the sign...

Let M be the magnetic moment of a system. Below are the Bloch equations, including the relaxation terms. dM_x/dt=({\bf M} \times \gamma {\bf H_0})_x-M_x/T_2 dM_y/dt=({\bf M} \times \gamma {\bf H_0})_y-M_y/T_2 dM_z/dt=({\bf M} \times \gamma {\bf H_0})_z+(M_{\infty}-M_z)/T1 At t=0, {\bf...

Homework Statement Consider three charges in a triangle as shown. 1. What is the net electric force on the charge at the origin? 2. What is the direction of this force(between -180 and 180)? 3. What is the magnitude of the net electric field at the position of the charge at the...

I was doing some homework problems, and I came across a couple I didn't know. I then realized I must have screwed up my understanding on electrical forces. For an electrical force, if there are two protons, the force is k*q1*q2/r^2. The direction is in the opposite direction. <---(+)...

Homework Statement In the figure, what is the force on charge Q3? Q1 = 5×10-6C, Q2 = -3×10-6C, Q3 = 4×10-6C http://www.usi.edu/science/physics/pickett/206/4p2f1.jpg Homework Equations Coulomb's law The Attempt at a Solution I thought I could just find the charges on q1 and 3 and...

This problem has been posted before with different values for each variable and I did as best I could to complete it similarly. However, when I attempt to input my final answer I get it wrong every time. I just wanted to see where I am going wrong, thanks. Homework Statement Coulomb's law...

Finding net force using velocity graph? The figure(Figure 1) shows the velocity graph of a 2.5object as it moves along the x-axis. What is the net force acting on this object at t=7 ? The attempt at a solution Since F=ma, I tried first finding a by dividing 6 m by 7 s. Then I...

Find the net electrical flux through a closed sphere of radius R in a uniform electric field I know that the flux is going to be 0 since there is no charge enclosed, but how would I show this mathematically? The next half of the question asks about a cylinder with sides parallel to the electric...

Homework Statement Calculate the net force acting on each object indicated in the following diagrams. Homework Equations c^2 = a^2 + b^2 sinA/a = sinB/b = sinC/c c^2 = a^2 + b^2 - 2abcosC The Attempt at a Solution Fnet =? Fnet(v) = 8.0 N [N] + 10.0 N [S] = 10.0 N [S] - 8.0 N [N]...

Homework Statement I am looking for some clarity on what should be general conceptual questions involving work, net work, and work done by friction. In General; W[F]=the component of the applied force acting in the direction of motion X distance OR Δenergy W[friction]=μN and is...

Three students converge on the last textbook in the store. All three grab it and begin to pull in the directions shown in the above figure. Student A exerts a force of 61.88 N, student B pulls with a force of 31.92 N, and student C pulls with a force of 104.20 N at an angle θ(theta)=80.8 degrees...

Suppose you have many forces acting on an object, and the object moves in space in some time interval. Each force has done some work on the object. Suppose you took all these values for work, added them up, (they are all scalars). You'd obtain a scalar equal to the net work done on the object...

Hi All, I was searching for Analysis course that typically follows Spivak's Calculus. While searching the Net came across this post below and have couple questions if you don't mind: My questions: 1. "Rigorous Advanced Calculus (Loomis and Sternberg)". Is that a single book or two...

Homework Statement A helicopter, starting from rest, accelerates straight up from the roof of a hospital. The lifting force does work in raising the helicopter. An 720-kg helicopter rises from rest to a speed of 7.5 m/s in a time of 5.0 s. During this time it climbs to a height of 7.9 m...

Homework Statement In my physics book (Young and Freedman 12 edition), in the chapter about conservation of energy, it teaches me that I can use the theory of conservation of energy and discover the velocity at the bottom of a circular path, having the height of this circular path. I...

Homework Statement For the dipole shown, the charges are ± 3.0 micro coulombs separated by a distance of 3.20 nm and oriented so that the theta is 35.0 degrees. If the electric field has a magnitude of 8000 N/C, find the magnitude and direction (clockwise/counterclockwise) of the net torque...

When we talk about rotational motion. I know what is the purpose of angular acceleration. We can get tangential acc. which accelerated the v tangential. Fine. Again, centripetal or radial acceleration for the change in direction but WHAT IS THE NEED TO KNOW THE LINEAR NET ACCELERATION? Take an...

Homework Statement A charge +Q exists at a point and directly west of this point a charge -Q exists. What is the direction of the net electric field at the midway point? I'm studying old finals for my exam and this question keeps popping up in various forms. The answer is always directed...