What is Net: Definition and 1000 Discussions

Does the ball clear the net?? Please help, thanks in advance? A tennis player hits a ball 2.0m above the ground. The ball leaves his racquet with a speed of 22.0m/s at an angle 4.5 degrees above the horizontal. The horizontal distance to the net is 7.0 m, and the net is 1.0 high. i know that...

Homework Statement a boat is a drift in a stream that flows at 3 mph 40* north of east. A wind blowing at 11 mph from a direction 50*NW also moves the boat. What will be the net direction and speed of the boat? Homework Equations Vwa = 3mph 40* NE Vwi = 11mph 50* NW The Attempt at...

Homework Statement li have three charges, 2 with same charge (magnitude and sign) and 1 with a smaller charge(smaller magnitude and opposite sign to the other two). how would i position them on a line so that the net force on any of them is zero Homework Equations electric force, F =...

Homework Statement Blue charge is at origin with positive q charge Red charge at point (d1,0) with unknown positive charge q_red Yellow charge at point (d2cos(theta),-d2sin(theta)) with negative 2q charge The net electric force on the blue sphere has a magnitude F and is directed in the...

Homework Statement Particle 0 experiences a repulsion from particle 1 and an attraction toward particle 2. For certain values of d_1 and d_2, the repulsion and attraction should balance each other, resulting in no net force. For what ratio d_1/d_2 is there no net force on particle 0...

Homework Statement A proton is on the x-axis at x = 1.2 nm. An electron is on the y-axis at y = 1.2 nm. Find the net force the two exert on a helium nucleus (charge +2e) at the origin. Express your answer using two significant figures. Enter your answers numerically separated by a comma...

This is a fairly simple Question but I just can't figure it out. If there is an object and there are two forces that act on the 5 kg object (say this object is located on the origin of an sy plane) and F1= 25 N and points in the 0 degrees direction and the other force, F2= 15 N and points 60...

Homework Statement "A derrick boom is guyed by cables AC and AD. A worker is lifting a 20kg block by pulling on a rope that passes through the pulley at A. Knowing that the boom AB exerts a force A that is directed from B to A, determine this force and the force in each of the two cables."...

Homework Statement Two charges are placed on the x axis. One charge (q1 = +16.5 µC) is at x1 = +3.0 cm and the other (q2 = -19 µC) is at x2 = +9.0 cm. Find the net electric field (magnitude and direction) at the following locations. (a) x = 0 cm magnitude= ? N/C direction= ? (b)...

Homework Statement We are given that one infinite line of charge is placed horizontally on the x axis. The other line charge is placed parallel to the first at y = 0.4m. The first line has charge density 4.8 * 10^(-6) C/m, and the second -2.4 * 10^(-6) C/m. Find the net electric field at the...

Homework Statement Consider the following situation: http://img206.imageshack.us/img206/9739/fbdow8.th.jpg The height of the incline is 'h'. a) Find the net acceleration of the centre of mass of the combined system (of the incline and the block) relative to ground. b) Find the speed of...

Homework Statement In the figure below, the incline is frictionless and the string passes through the centre of mass of each block. The pulley has moment of inertia I and radius R. a) Find the net torque acting on the system (the two masses, string and pulley) about the centre of the pulley...

Homework Statement Two identical dipoles, each of charge q and separation a, are a distance x apart, as shown in Fig. By considering forces between pairs of charges in the different dipoles, calculate the net force between the dipoles. Show that, in the limit a<<x, the force has magnitude...

Homework Statement Two nonconducting spheres, of r1=3.0cm and r2=2.0cm, are placed of an x-axis. They have surface charge densities of +6.0mC/m2 and +4.0 mC/m2, respectively, on their outside surfaces. The center of sphere r1 is on the origin and the center of sphere r2 is 10 cm away. What is...

Im having a bit of trouble understanding this and hoping someone can give me an idea how to understand and calculate net displacement of 3 different directions and distances?

Two positive charges q0 at the origin and q1 at (0,d1,0) and one negative charge -q2 at (0,d2,0). What is the net force on particle 0 from particle 1 and 2? (See Picture CPartB inserted at bottom) F on 0 due to 1 = kq0q1/d1^2 and since it is in the negative y direction since q1 repels q0...

Hi all, I am having difficulty in understanding this basic phyics relating to force, work,and movement, and I am struggling to do these questions. I would appreciate any help. The following information was provided and then three questions followed. A boy drags a box by a rope across a level...

Homework Statement The balanced net ionic equation for precipitation of CaCO3 when aqueous solutions of Na2CO3 and CaCl2 are mixed is _____. Homework Equations Not sure of any The Attempt at a Solution I'm not sure how to get a "net ionic equation." I took chemistry 2 years ago and...

http://www.businessweek.com/technology/content/jul2008/tc20080711_699714.htm?chan=top+news_top+news+index_technology What are your opinions on net neutrality, and how it should be protected (or not protected)?

What happens when the NET force on a massless body is 0. I mean what will be the acceleration , if any? Also if we pull a massless spring, from one side with a force F1 and from the other side a force F2, what will be the spring force?

Homework Statement A mass of 500 g is attached to the bottom of an unstretched spring attached to the ceiling, and has a spring constant 10 N/m. The mass is then released. What is the net work done on the mass between the point where it was released and the lowest point that it reaches...

Homework Statement A 3.00 Kg object is moving in a plane, with its x and y coordinates given by x=5t^2-1 and y=3t^3+2, where x and y in meters and t in seconds. Find the magnitude of the net force acting on this object at t=2.00 secs. Homework Equations The Attempt at a Solution...

Homework Statement During a tennis match, a player serves the ball at 25.3 m/s, with the center of the ball leaving the racquet horizontally 2.50 m above the court surface. The net is 12.0 m away and 0.900 m high. When the ball reaches the net, (a) what is the distance between the center of...

Homework Statement In a cathode ray tube, electrons are accelerated from rest by a constant electric force of magnitude 6.4E-17 N during the first 2.0cm of the tubes length; then they move at essentially constant velocity another 45cm before hitting the screen. A) Find the speed of the...

Homework Statement The box-like Gaussian surface of the figure below encloses a net charge of +57.0ε0 C and lies in an electric field given by = [(10.3 + 2.4x)·i - 3.1·j + bz·k ] N/C, with x and z in meters and b a constant. The bottom face is in the xz plane; the top face is in the...

[SOLVED] Two point charges, Zero Net Force Homework Statement Two point charges of charge 7.40 μC and -1.80 μC are placed along the x-axis at x = 0.000 m and x = 0.300 m respectively. Where must a third charge, q, be placed along the x-axis so that it does not experience any net force because...

Homework Statement Make the following into a web address; it wouldn't let me post one. img161.imageshack.us/img161/3728/physicspv5.pngimg161.imageshack.us/img161/3728/physicspv5.b3825b8665.jpg[/url] What is the net torque on this object? Homework Equations torque=(radius)(force)(sin(...

I'm trying to write a Library entry on Reaction Force, and I've discovered I can't answer this very simple question. :redface: Two equal blocks are on a horizontal table, with a gap between them. A straight rod is placed above the gap, but not symmetrically, resting on both blocks, with an...

The Earth is effectively an insulator in space, and the sun continuously beats on the Earth with protons, electrons and other particles. Does the planet Earth and all other planets have a net charge, and if so, how can we measure the polarity and extent of that charge? Turning to the Sun...

Homework Statement What is the net change in entropy of the system from the time of mixing until the moment the ice completely melts? The heat of fusion of ice is . Note that since the amount of ice is relatively small, the temperature of the water remains nearly constant throughout the...

Hello everyone, Could someone please help me with this problem? Homework Statement A 145kg object and a 445kg object are separated by .420m. a. Find the net gravitational force exerted by these objects on a 41.0kg object placed midway between them. b. At what position can the 41.0kg...

Homework Statement The speed of a particle doubles and then doubles again because a net external force acts on it. Does the net force do more work during the first or the second doubling? Justify your answer. Homework Equations I'm not sure, but i think E = 1/2 mv(squared) The...

A sailboat is moving at a constant velocity. Is work being done by a net external force acting on the boat? Explain. The speed of a particle doubles and then doubles again because a net external force acts on it. Does the net force do more work during the first or the second doubling...

Wnc = delta (kinetic energy) + delta(potential energy) (Work done by nonconservative forces) = (change in kinetic energy) + (change in potential energy) Now, my professor gave us this formula instead of the one above: W - H = (change in kinetic energy) + (change in potential energy)...

I have a problem in trying to express a net force equation for a falling elastic object when collision ensues. For instance, you drop a spring with a spring coefficient k. the spring compresses a distance x after a time t for a maximum time of tf and distance xf. the spring has a weight W...

Homework Statement An emtpy rubber balloon has a mass of 0.0120 kg. The balloon is filled with helium at 0 degrees Celcius, 1 atm pressure, and a density of 0.179 kg / m3. The filled balloon has a radius of 0.500 m. A. What is the magnitude of the buoyant force acting on the balloon...

Homework Statement The Bruce Nuclear Development is a CANDU style reactor. This means that it has a "vaccum building" to "suck" (the contents of a malfunction reactor to a safer place. Refer to the engineering "specs" for the needed information to calculate the net force of the atmposhere...

A plane is diving toward the ground and then climbs back upwards as shown below. A lift force acts perpendicular to the plane's displacement, s = 1.7 x 10^{3} m, which should be taken to be the same for each case. The engines of the plane exert a thrust as shown which has the same magnitude...

[SOLVED] Net Force of object changing velocity Hi, I'm studying for a test, so there might be a few of these in the next hour or so. Homework Statement A supertanker of mass 1.0 X 10^{8} kg travels 3.5km, reaching a speed of 4.1km/h from rest. What was the magnitude of the unbalanced force...

[SOLVED] I really need help I understand the very simple questions and all, but when the book throws all these extra things at me, I get so lost. You might've remembered my earlier post (my first one), so I'm back with a bit more. If it takes a human cannonball 1.5s to exit a 1.6m long...

A constant nonzero net torque is exerted on an object. Which of the following can not be constant? Choose all that apply. -angular position -angular velocity -angular acceleration -location of center of mass -moment of inertia -kinetic energy My guess is...

I'm having trouble understanding the CNIE process. It would be very much appreciated if someone could show me how to solve a sample problem.

Harvard has now put up streaming videos of Sidney Coleman’s 1975-1976 Quantum Field Theory lectures. Bryan Chen has also transcribed the first eleven lectures to TeX format!. http://www.physics.harvard.edu/about/Phys253.html http://www.physics.upenn.edu/~chb/ So, good for anybody that's...

Homework Statement will a body necessarily remain at rest if the net force acting on it is zero?give a reason for ur answer...and I've just passed my ninth grade so if u cud please it to me explain at that level...:smile: Homework Equations The Attempt at a Solution

A ballerian spins initially at 1.5rev/s when arms are extended. She then draws in her arms to her body and her moment of intertia is .88kg m^2 and her angular speed increases to 4.0rev/s. Determine the network she did to increase her angular speed? To find moment of inertia was pretty simple...

A ballerian spins initially at 1.5rev/s when arms are extended. She then draws in her arms to her body and her moment of intertia is .88kg m^2 and her angular speed increases to 4.0rev/s. Determine the network she did to increase her angular speed? So i first needed to solve for the initial...

A toy car of mass 50g travels down a smooth incline at 30 degrees to the horizontal. Friction can be ignored. Also Gravity is assumed to be 10ms Calculate the net force on the car as it rolls down the slope: For this I use M x G sin 30 so .05 x 10 sin 30 and got .25N - Hopefully...

The figure below shows plots of the current i through a certain cross section of a wire over four different time periods. Rank the periods according to the net charge that passes through the cross section during the period, greatest first. (Use only the symbols > or =, for example a>b=c>d.)...

Forces/Friction I'm new, so I'd like to say thanks in advance for helping me. The site wants all answers to the 4th decimal place. Idk how stuff normally works around here, but a small explanation with the answer would help me understand this stuff better. 1. Three forces act on a particle...

Can anyone help me through this net ionic equation problem? Pb(ClO4)2 (aq) +NaI (aq) -> PbI2 (s) + NaClO4 (aq)