# Search results

1. ### Effect of Strain Hardening on Yield Strength

Homework Statement The strain hardening behavior of an annealed, low‐carbon steel is σ = 100,000ε0.2 If a bar of this material is initially cold worked 20%, followed by additional cold work of 30%, determine the probable yield strength of the final bar. Homework Equations σ=κεη...
2. ### FBDs and Tension

Homework Statement While working through problems I always have trouble determining the direction that tension acts in on objects in the system. In system B.) block A has a velocity of 4m/s to the right, with mu(k)=0.2, causing the mass B to fall, in class tension was assumed to be in the...
3. ### Heat Transfer

Homework Statement An electrical wire 1/8" in diameter is covered with insulation 3/32" thick. Six watss of electrical energy are dissipated as heat by the resistance of the wire per foot length. The heat is given up to the surrounding air at 60 degrees farneheit. Estimate the outside...
4. ### Fluid Mechanics - Distance to Centroid

Homework Statement http://i284.photobucket.com/albums/ll12/uradnky/fluid.jpg I'm asked to solve for the force on the projected plane surface and show where it is acting. This problem seems pretty easy, but with the dimensions given I can't find Lc, so I cant find dc to begin it. Is...
5. ### Conservation of Energy - Roller Coaster

Homework Statement A roller coaster car has a mass of 800kg. It is released from the top of the hill A and moves without friction down the track. Determine the minimum exit velocity vD at ground level so that the car travels around both the circular loops (Loop B - Radius= 10m, Loop C -...
6. ### Area under curve

Homework Statement Find the area bound by y= x - 2\sqrt{x} and y=0 The Attempt at a Solution X intercept = 4 Y intercept = 0 Using verticle rectangles.. dA = ((Upper curve)-(Lower curve)) dx \int(dA = \int(0-(x-2\sqrt{x})) dx A= -(1/2X^2)-((2x^(3/2))/(2/3)) Evaluated from...
7. ### Applications of Integrals

Homework Statement In coming to a stop the acceleration of a car is given as a= -4t. If it is traveling at 32m/s when the brakes are applied, how far does is travel while stopping? The Attempt at a Solution 1.) Integrate acceleration to find velocity as a function of time v=...
8. ### Calculus - Max/Min

Homework Statement The electric power in Watts produced is given by p= 144r/(r+.8)^2 where r is the resistance in ohms. For what value of r is the power P a maximum? Homework Equations The Attempt at a Solution Using the quotient rule i found a derivative of.. dp/dt= 144(-r+.8)...
9. ### Related Rates height of rising water

Homework Statement A rectangular swimming pool 16m x 10m is being filled at a rate of .8m^3/min. How fast is height of the water rising? Homework Equations V = LWH The Attempt at a Solution H = V/LW (dh/dt) = LW(dv/dt) (dh/dt) = (10)(16)(.8) This question looks so easy...
10. ### Statics - Method of Members

What is the easiest way to determine the two force member in a frame question? When I look at a frame and see the pinned connections, I automatically assume that there is a reaction in the x and y directions. How can I tell at which pin there is only one reaction, and what direction it is...