Wall Definition and 735 Threads

Homework Statement A uniform 15 kg ladder whose length is 5.0 m stands on the floor and leans against a vertical wall, making an angle of 25 degrees with the vertical. Assuming that the friction between the ladder and the wall is negligible, what is the minimum amount of friction between the...

so I have a brick wall in my room I want to put a poster on. it's the regular small house brick, a chimney to be exact. I've used sticky tack and tape. both hold for a bit and let go after a couple weeks. what would you use?

Homework Statement Air within the funnel of a large tornado may have a pressure of only 0.2 atm. Atmospheric pressure is 101300 Pa. What is the approximate outward force F on a 11m X 16 m wall if a tornado suddenly envelopes the house? Answer in units of N. Homework Equations P = F/A...

[b]1. The problem is: A vertical wall (5.9m x2.5m) in a house faces due east. A uniform electric field has a magnitude of 150 N/C. This field is parallel to the ground and points 35degrees north of east. What is the electric flux through the wall? [b]2. Homework Equations : Electric...

If two planes of mirrors (infinite in all directions) were facing each other with nothing in between what would they reflect? How does light come into play in this? If they were not directly stuck to each other (in which case there would be absolute black, no light I assume) but at a distance...

[FONT="Garamond"]If two planes of mirrors (infinite in all directions) were facing each other with nothing in between what would they reflect? How does light come into play in this?

Hello! I'm considering the purchase of a 100 pound LCD television. I anticipate mounting it with an articulating mounting system. The mounting system will allow the television to extend ~27 inches from the mounting wall (thereby creating a considerable torque load on the wall studs used)...

I was wondering if anyone could provide me with more information regarding DC-to-AC inverters. Specifically, I'm wondering what stops me from hooking up a power source (i.e. lead acid battery, small solar panel, etc) to an inverter and discharging it into the wall. I know that grid-tie systems...

How would you calculate the height needed to do a flip off the wall as described in http://www.wikihow.com/Run-up-a-Wall-and-Flip given the height of the person and the speed.

a ladder 4m long rests against a vertical wall. If the bottom of the ladder slides away from the wall at a speed of 30cm/s. How quickly is the top of the ladder sliding down the wall when the bottom of the ladder is 2m from the wall.

Given: a platform which is 4m high. On the edge of it is a brick wall with height Y. The launch site is some way behind the wall. The landing site is past the wall and beyond the platform. The launch angle is 40 degrees. Find the range. x=vot cos @ (where @=angle) y=vot sin @ range=(vo^2...

I came across this by accident. http://amasci.com/weird/unusual/e-wall.html. David Swenson of 3M Corporation describes an anomaly where workers encountered a strange "invisible wall" in the area under a fast-moving sheet of electrically charged polypropelene film in a factory. This...

Milton Friedman said that the depression that started in 1929 resulted from banks losing their nerve and failing to shore up the US economy.Was he right?

A 9 kg steel ball strikes a wall with a speed of 10 m/s at an angle of 49.8 degrees with the normal to the wall. It bounces off with the same speed and angle. If the ball is in contact with the wall for .0911 sec, what is the magnitude of the average force exerted on the ball by the wall...

Homework Statement resonant freq. in air for arbitrary length steel pipe with radius in the 3-8 cm range and wall thickness in the o.5 to 1 cm range Homework Equations unable to find a relevant equation The Attempt at a Solution

A large aquarium of height 5.00m is filled with fresh water to a depth of 2.00m. One wall of the aquarium consists of thick plastic of 8.00m wide. By how much does the total force on that wall increase if the aquarium is next filled to a depth of 4.00m.

Here's a question (not homework) that someone asked me a few days ago: you have a rod with length L and mass M that's leaning against a frictionless wall and makes a 30deg angle with the floor. what does the static friction have to be inorder for the stick to stay inequilibrium? What i did...

A bullet with an initial velocity of v0, temperature t0(melting temperature), goes through a wall, and its velocity reduces to v. You know Lb(latent specific heat). You are asked to derive the ratio between the final mass of the bulet and the initial one.Oh, and you know that the energy lost by...

Homework Statement A uniform ladder with mass m2 and length L rests against a smooth wall. A do-it-yourself enthusiast of mass m1 stands on the ladder a distance d from the bottom (measured along the ladder). The ladder makes an angle x with the ground. There is no friction between the wall...

A ball of mass m moving with velocity v_i_vec strikes a vertical wall. View Figure The angle between the ball's initial velocity vector and the wall is theta_i as shown on the diagram, which depicts the situation as seen from above. The duration of the collision between the ball and the wall...

Hi. I've tried to answer this questions four times and so far none of my answers have been correct. Any help is greatly appreciated! A uniform 48 kg (m) beam at an angle of 24 degrees (theta) with respect to the horizontal has length of 38 m (L). It is supported by a pin and horizontal cable...

Hi, I'm new to this forum and I have a question. In my physics class we are discussing energy and work. We are given this problem: "It is exactly 0*C. How fast must you throw a snowball against a wall in order to make it completely melt? (Assume all the energy is transferred to the...

Small ice cubes, each of mass 5.30 g, slide down a frictionless ski-jump track in a steady stream, as shown in Figure P6.71. Starting from rest, each cube moves down through a net vertical distance of y = 1.40 m and leaves the bottom end of the track at an angle of 40.0° above the horizontal. At...

A 57.0 g tennis ball with an initial speed of 25.2 m/s hits a wall and rebounds with the same speed. The figure below shows the force of the wall on the ball during the collision. What is the value of Fmax, the maximum value of the contact force during the collision, if the force is applied for...

Okay I know this should be easy but for some reason I just can't get it. "You throw a ball toward a wall with a speed of 25.0 m/s and at an angle of 40.0 degrees above the horizontal. The wall is 22.0 m from the release point of the ball. (a) How far above the release point does the ball...

Hints, please? "An arterial aneurysm is a life threatening condition associated with a balloon like expansion of a local segment of an artery. Using a free body diagram determine the average wall stresses in a closed spherical aneurysm with wall thickness h and inner radius r_i. Ignore blood...

A tennis ball with a speed of 25.1 m/s is moving perpendicualr to a wall. After striking the wall, the ball rebounds in the opposite direction with a speed of 12.8 m/s. Take "twords the wall" to be a positive direction. If the ball is in contact with the wall for 0.0105 s, what is the average...

The rod shall be replaced by a tube (wall thickness s = da=12).if da is the outer diameter,then the inner diameter is it di=da-da/12 ??

Get into the wall ! I want to say that we can't go into the wall b'cus we know that we are made up of atoms (mainly electrons, protons and neutrons) and all these are fermions, and so as wall. Since fermions follow Pauli's Exclusion Principle. Suppose, we get inside the wall so the fermions...

an object is connected to the wall through a spring and is resting at its equilibrium position. its mass is M and the coefficient of kinetic friction is 1/4. the object is flicked so that it will return to its original position (not instantly, but its oscillation is damped slowly). what is...

A uniform ladder of length 9 m leans against a frictionless vertical wall making an angle of 47° with the ground. The coefficient of static friction between the ladder and the ground is 0.41. If your mass is 74 kg and the ladder's mass is 33 kg, how far up the ladder can you climb before it...

Besides the cost, what is wrong with building a wall on the Mexico/America border? I don't see how this could be morally wrong, or wrong in any other way besides the cost of the thing.

Hi, my question is this: A solid ball with mass M, radius R, speed U0, angular speed W0 hits a wall at the angle theta0. after the hit, the ball goes away with an angle theta1, angular speed W1 and speed U1. i'm asked to find the angular momentum for the point of hit, before and after the...

I was having an argument with my sister last night about the limits of scientific knowledge (her beliefs encompass a more "spiritual" world view than mine) and she brought up quantum mechanics as an example of how weird things are possible (as peddlers of hocus-pocus love doing). Leaving aside...

What are blast walls made of? Something like plexiglass or something? How would I go about doing this? Something like on Mythbusters, I want to be able to see through it, while having some protection.

http://famulus.msnbc.com/famulusgen/ap01-24-163025.asp?t=apnew&vts=12420061708 Microsoft's average daily volume is ~62 million. Microsoft's shares are up $0.02 in after-hours trading (when the news report came out) :smile: :smile: :smile:

An aluminum tube with an outside diameter of 1,000 in. will be used to support a 10-kip load. If the axial stress in the member must be limited to 30 ksi T or C, determine the wall thickness required for the tube. I used tau=shearing stress/area therefore 30(pie times 1-d)=10 but that is not...

does anybody know the rules to find minimum velocy in a rod laying against the wall with specific angle??

can anyone of u tell me is it possible by the present quantum state that we become pure energy at a position x and move to another location by the prpagation of energy as wave and reappear as particle at another location y

A 1.29-m long ladder weighing 200N rests against a vertical wall so that the top of the ladder is at a height of .590m. A 603-N man stands on the ladder at a distance of .390m along the ladder. Calculate the force exerted by the wall on the ladder. Assume that the wall is perfectly smooth...

Just curious. This is my new wall paper. I got tired of my old one. I just bought a new Maxtor external hard drive that holds 100 gigs. I have two computers in my house networked, so I took ALL the files from both computers and put it on the external drive and made that drive on the network as...

An above-ground backyard swimming pool is shaped like a large hockey puck, with a circular bottom and a vertical wall forming its perimeter. The diameter of the pool is 4.9 m and its depth is 1.3 m. Find the total outward force exerted on the vertical wall of the pool. so P= F / A and i used...

Is it possible for a torch to light up a wall, but not reflect back to you so that you cannot in fact see the light hitting the wall? For instance I can see streetlights from a couple of miles away out of my bedroom window - therefore the light from the streetlights must be reaching me - but...

there is two rooms in one of them ,i lit a red bulb and in the other room a white bulb when I'm in the red room i see the wall that is between these two room,red,but when I'm in the room with white light i see this wall white. why?

The problem states: a 0.13-kg meter stick is held perpendicular to a wall by a 2.5-m string going from the wall to the far end of the stick. (a) find the tension in the string; (b) if a shorter string is used, will its tension be greater than, less than, or the same as that found in part (a)...

A uniform board is leaning against a smooth vertical wall. The board is at an angle above the horizontal ground. The coefficient of static friction between the ground and the lower end of the board is 0.350. Find the smallest value for the angle , such that the lower end of the board does not...

Ok I have had a course is general relativity, but not on special. I was wondering something though... If you have a brick wall a light year long (when at rest) and then have it thrusted at you at a speed such that it is only 1ft long, i.e. .99999c, when would you be able to stand in front of...

This 5.0 kg block is pushed 3.0 m up a vertical wall with constant speed by a constant force of magnitude F applied at an angle of theta = 30 degrees with the horizontal. mu kenetic = .30 between wall and block. I need to a). determine the work done by F, b) the force of gravity and c) the...

Hello, I got this problem from a book "A light ladder leans against a perfetly smooth vertical wall at an angle of 30 degrees to the horizontal. A load of 800N is placed 3-quarters of the way up the ladder. If the ladder rests on a rough horizontal surface which prevents slipping, find the...

A sound wave travels at a frequency 2.25 MHz through a pregnant woman's abdomen and is reflected from the fetal heart wall of her unborn baby. The heart wall is moving toward the sound receiver as the heart beats. The reflected sound is then mixed with the transmitted sound, and 87.0 beats per...