Net Definition and 1000 Threads

Hello, I've just got a quick question about charging an object by conduction. I've been studying for my final and I came across a problem that I can't really see how to solve. Say you have two conducting spheres, A and B. They are both exactly the same in every way except for their electric...

A ball is thrown upward at 90 ft/sec from the top of a 6 story building. How long will it take before the ball lands on the sidewalk below? This is what I have so far: _{0}∫^{t} 90t dt General statement for the fundamental theorem of calculus (_{a}∫^{b} f(x) dx=F(b)-F(a)).

A 2.0 kg mass starts from rest and slides down an inclined plane 8.0 x 10^-1 m long in 0.50 sec. What net force is acting on the mass along the incline? Can someone please explain step by step in a descriptive way. I have a quiz tomorrow and I just can't even start this problem

Homework Statement Three masses m, 2m and 3m are placed on a horizontal surface. A force F is shown acting on m3. Assuming μs,k is the same between all of the masses and the horizontal surface, answer the following: a) Find the expression for the net force on the 2m mass. b) For F constant...

In Fig. 10.45, block 1 has mass m1=460g, block 2 has mass m2=500g, and the pulley, which is mounted on a horizontal axle with negligible friction ahs radius R=5.0cm. When released from rest, block 2 falls 75.0cm in 5.00 s without the cord slipping on the pulley. (e) What is its rotational...

Homework Statement The sum of the net torques is zero even f the numerical result is not. Rather than simply explaining that the net torque is close to zero, justify that your net torque is small, within the context of this experiment. 2. Attached is a pdf of the lab that we had this...

Homework Statement An objects momentum is given by the following equation p(t) = 4t3-6t+1. What net force is acting on the objects at t=2?Homework Equations P=m*v F=Δp/ΔtThe Attempt at a Solution So, I was thinking if F=m*a I can change a and get F=m*(Δv/Δt) and knowing what I know about p...

Hello all! I want to know the difference between growth rate and net growth rate(the context is broad-population or economic,take it as you may).

THANKS, I ONLY NEED HELP #2 NOW, PLEASE 10/31/12 @ 9:10 pm bumpHomework Statement 1)If the fulcrum of a 0.1 kg meter stick was placed at the 40 cm mark and a 200 g mass at the 0 cm mark, would it be possible to balance the meter stick with a 200 g mass on the long side of the meter stick? What...

1.Two concurrent forces act on a box. The first force acts east at 13 Newtons and the second force acts west at 17 Newtons. What is the net force acting on the box? >Draw each vector using the tip to tail method. >Draw your resultant and label it "R" >With your ruler determine the...

okay well basically this is what i know or think i know: i have the pKa's of the carboxyl, amino, and R group of the amino acid and the pH of the solution it is in. I'm supposed to figure out the net charge for it at different pHs. i taught myself one way to do it (by looking **** up) and i...

Homework Statement You are given 3 wires parallel to each other (1)------> I (2)<-------I (3)------->I http://www.webassign.net/knight/p32-38alt1.gif (not sure it this link works) I1=I2=I3 = 16A the distance between the wires is d=2cm length of the wires is l= 50cm Homework Equations I...

Homework Statement Three masses (m1 = 4.4 kg, m2 = 13.2 kg and m3 = 8.8) hang from three identical springs in a motionless elevator. The springs all have the same spring constant, which is 268 N/m. The elevator is moving downward with a velocity of v = -3.7 m/s but accelerating downward at...

A toy hovercraft has a mass of 914g. Each of the two fans pushes back on the air with a force of 0.38 N. a. If there's no friction acting on the hovercraft, what is the net force acting on it? b. What is the acceleration of the hovercraft? c. If you start with the hovercraft at rest, and...

Homework Statement Dough boy took a ride in his new car, he hammers the throttle in 2 seconds and his velocity is 45 km/hr (assume constant acceleration). The mass of the Viper is approximately 800kg, Find the net force acting on the viper. To be honest I am clueless on this question, I have...

Homework Statement Is it ever alright to consider net acceleration as equalling acceleration forward - acceleration backward Here's the scenario: I have a string rotating a wheel at 9.8 m/s^2 ( which I have converted to Angular Acceleration using a = α * r There will be friction acting...

Homework Statement 2 kg mass swings on the end of a rope as shown in the figure below. At the highest point in the trajectory the string makes a 56 degree angle with respect to the horizontal and the tension on the string is 16.25 N. = (No Response) N Homework Equations So I know I need to...

Homework Statement We are given a belief network such that the overall joint probability after accounting for conditional independence is: P(a,b,c,d,e) = P(a)P(c|a,b)P(d|b)P(e|d,b) The values provided are: P(a = false) = .02 P(b = false) = .95 P(c= false|a=true, b=true) = .97 P(c=...

The integral form of gauss's law is used to determine the electric field of charge distributions which possesses a certain amount of symmetry. Now imagine using it in situations where the gaussian surface includes equal amounts of positive and negative charge. For example,imagine a point...

Homework Statement q1= 6.7 μC q2= -4.5 μC q3= 2.2 μC q4= 2.2 μC d= 7.7 cmWhat is the x-component of the net force on q1? Homework Equations The Attempt at a Solution This is part of an online problem set, and is currently the only question I have not answered correctly. I find it strange...

Homework Statement The HCl (hydrochloric acid) molecule has a dipole moment of about 3.4x10-30 C.m. The two atoms are separated by about 1.10-10 m. What is the net charge on each atom? What is maximal torque that this dipole will experience in a 5.104 N/C electric field? How much energy one...

Homework Statement Two blocks, of masses m1 = 10kg and m2 = 5kg respectively are connected by a massless unstretchable string and are pulled by an applied force Fa, up a frictionless incline which makes an angle of θ=30° with the horizontal. The tension in the string which connects the two...

I am studying for my exam and I have run into this problem. The problem is given here http://faculty.mint.ua.edu/~pleclair/PH253/Homework/Spring_2010/HW6-7_atoms_12Mar10/HW6-7_atoms_12Mar10_SOLN.pdf"],[/PLAIN] it is #9. I don't understand why -e ≠ ∫ρdV from 0 to the bohr radius, a0. If all...

http://physicsworld.com/cws/article/news/2011/jul/25/was-the-universe-born-spinning http://arxiv.org/ftp/arxiv/papers/1111/1111.3873.pdf Is there any particular reason why the universe cannot have a net angular momentum? If it did indeed have a net angular momentum are there any...

Homework Statement Four charges, q1 = +195 µC, q2 = +60 µC, q3 = −145 µC, and q4 = +21 µC, are fixed at the corners of a 4 m by 5 m rectangle, as illustrated in the figure below. What are the magnitude and the direction of the net force acting on q1? (Assume the x-axis extends from q1 to...

I read in my textbook that an object can have constant velocity when net force and acceleration are equal to 0. For an example like a puck on frictionless ice that continues to move after it has had a force applied to it that is all good and fine, I understand that inertia keeps the puck moving...

I was wondering if someone could help me with this question: A charge 3q is at the origin, and a charge -2q is on the positive x-axis at x = a. Where would you place a third charge so it would experience no net electric force? I currently set up two equations: 1. 3q*q/b^2 where b is...

Homework Statement Lifting a 20lb bucket of sand a distance of 100 ft at a rate of 2ft/s. I would assume: [W=F*d] = [W = MA*d] = [W = M(v/t)*d] and at a constant velocity: rate of v/t=0 so [W = M(0)*d] = [W = 0*d] = [W = 0] However, a video online shows that you'd take 20lb*100 ft...

Just a thread to post funny pictures you found on the net. I searched but didn't find a thread for this. Hopefully I'm not wrong.

Both arrows have the same angles http://imageshack.us/photo/my-images/337/drawingz.png/ How can I find the net force of this and the direction ? Thanks.

Homework Statement A spring has a relaxed length of 20 cm (0.20 m) and its spring stiffness is 9 N/m. You glue a 80 gram block (0.08 kg) to the top of the spring, and push the block down, compressing the spring so its total length is 10 cm. You make sure the block is at rest, then at time t =...

1. What is the net force on a cart that is pulled to the right with 100 pounds and to the left with 30 pounds? Changes in motion are produced by a force or combination of forces. A force, in the simplest sense is a push or a pull. Its source may be gravitational, electrical, magnetic, or...

I'm trying to explain to someone why I think the net acceleration of the Earth (due to the sun) is non-zero. My reasoning is that the velocity of the Earth is constantly changing. As the sun pulls the Earth's orbit into an ellipse, the direction component of velocity is being changed...

Homework Statement I need to find the net force of the following, I am pretty sure i know the answer, but i just wanted to check to see if i am actually doing it correctly Homework Equations i just need to find the net force (i have attached the question) The Attempt at a Solution...

Homework Statement In the circuit below, at time t = 0, the switch is closed, causing the capacitors to charge. The voltage across the battery is 12 V. **Image of circuit is attached. A)Calculate the time constant for the RC circuit B)Calculate the time required for the voltage across...

Homework Statement 4 identical charges each equal to Q are placed at the 4 vertices of a regular triangular pyramid of each side equal to 'a'. Find the net electrostatic force on anyone charge. Homework Equations F = kQ^2/a^2 The Attempt at a Solution find the force due to each...

Homework Statement A disk begins spinning from rest with angular acceleration @ = 12 rad/s^2. A small object is on the disk a distance r = 2.0 cm from the center. What is the magnitude of the net acceleration of the object after a time t = 0.25s? (alpha) @ = 12 rad/s^2 r = 2 cm t = 0.25 s...

Homework Statement Three object A, B and C are placed 5.00 x10^-1 m apart along a straight line. If A and B have equal masses of 10 kg and C has a mass of 15 kg what is the net gravitational force on B due to A and C? Homework Equations Fg= Gm1m2/r^2 Horizontal Fnet= Fa + Fg The...

A 4.0 x 101 kg wind sled is gliding East across a frozen lake at a constant speed of 12 m/s, when a gust of wind from the southwest exerts a constant force of 1.0 x 102 N on its sails for 3.0 s. With what velocity will the sled be moving after the wind has subsided?

Homework Statement Calculate the magnitude of the net force on an air parcel of mass 1.0x10-3kg which is at a temperature 250K and which is in the US standard atmosphere at an altitude of 4.0km. Take the lapse rate as 6.5K/km and the surface temperature as 288K Homework Equations Force =...

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?

Suppose I have an object moving in a free space at initial velocity of v (no friction). Then two forces of equal magnitude but opposite directions are applied on the moving object of which one of them is in the same direction as the moving object. Is there work done by that force?

Homework Statement Three parallel wires carry a current of I 1 = 3 A, I 2 = 2 A, and I 3 = 1 A, respectively. They are arranged as shown. If r = 2m and L=5m,what is the magnitude of the net force on the bottom wire? <------------------------- I1 r -------------------------->I2 2r...

Work is defined as force times displacement. When the force is applied on an object which does not move, or is applied perpendicular to the direction of motion, the work done is zero. So let's say I hold an object with a mass of 1 kg still in the air for 10 seconds. Because the object does...

Homework Statement Two particles are fixed to an x axis, particle 1 of charge q1 = 2.1x10^-7 C at x = 20cm and particle 2 of charge q2 = -4.00q1 at x = 70cm. At what coordinates on the axis is the net electric field produced equal to 0? Homework Equations The Attempt at a Solution...

The first law seems obvious, plug in 0 for acceleration and you get 0 force. Therefore for something to accelerate there needs to be some net force. Also, wouldn't the third law have to be true if energy is conserved at all times? Sorry if this has been asked before.

Homework Statement Write a balanced net ionic equation for the following chemical reaction Homework Equations Cr^{3+} + ___NH3 (aq) + ____H2O (l) → Cr(OH)3 (s) + ___NH4^{+} (aq)The Attempt at a Solution The balanced molecular equation is Cr^{3+} + 3 NH3 (aq) + 3 H2O (l) → Cr(OH)3 (s) +...

Why does a body accelerate when it experiences a net force? Is there any change in molecular state of the body when it experiences a force?

Point charges q1 and q2 lie on the x-axis at points x = -a and x = +a, respectively. (a) How must q1 and q2 be related for the net electrostatic force on point charge +Q, placed at x = +a=2, to be zero? (b) Repeat (a) but with point charge +Q now placed at x = +3a=2. Can someone help me...

I am internet illiterate, however, I would like to understand the net neutrality issue by, perhaps, this Monday 1:00 pm (approximately 63 hours from the time of this post). This is a topic in my textbook so it could become a topic I'll have to write or speak about later this semester. I'm sure...