Recent content by jennypear

thanks so much!

v=(1/pi*Ro) integral 20(1-R/Ro)^(1/7) 2*pi*R*dR i know that i need to change my variable started out y=Ro-R dy=-dR but haven't found a substitution that would get rid of my R variable

An engine with an output of 150W has an efficiency of 25%. It works at 10 cycles/s. A. How much work is done in each cycle? work=power(delta t) = 150 W * 1s = 150 J work =15.0 J per cycle **got part A correct B. How much heat is given off in each cycle? delta...

The specific heat of a 109-g block of material is to be determined. The block is placed in a 34.0-g copper calorimeter that also holds 52.0 g of water. The system is initially at 20.0°C. Then 140 g of water at 83.0°C are added to the calorimeter vessel. When thermal equilibrium is attained, the...

hmm tricky:) thanks so much will look at it that way in the future

so you are saying q(ice) + q(ice-water) = q(steam) + q(steam-water) 50025J + 4.18J/g*150g(Tf-273)=58682J + 4.18J/g*26g(Tf-373) 121146J + 627J*Tf = 58682J + 108J*Tf - 40538J 519J*Tf=139290J Tf=268degree K which is still wrong... did i understand you correctly?

An insulated bucket contains 150 g of ice at 0°C. If 26.0g of steam is injected at 100°C into the bucket, what is the final equilibrium temperature of the system in °C? this i what I've done so far q(ice)=150g*333.5J/g=50025J q(steam)=26g*2257J/g=58682J q(ice) + q(ice-water) =...

so that would be F=deltaP*A .35*.32^2=.03584 that came up as incorrect

how do you account for that?

A cubic metal box with sides 32.0 cm contains air at a pressure of 1.00 atm and a temperature of 294 K. The box is sealed so that the volume is constant and it is heated to a temperature of 396K. Find the force on each wall of the box due to the increased pressure within the box. [The outside...

Propane, C3H8(g), is used in many instances to produce heat by burning: C3H8(g) + 5O2(g) --> 3CO2(g) + 4H2O(g) The standard enthalpy of reaction, , is -2,044 kJ. How many grams of oxygen would be needed to react with excess propane to produce 213.0 kJ of heat? heat of formation of...

nevermind I got it. I forgot to add the initial 3.78m the train traveled before the person started running.

A train pulls away from a station with a constant acceleration of 0.21 m/s2. A passenger arrives at the track 6.0 s after the end of the train passed the very same point. What is the slowest constant speed at which she can run and catch the train? Xtrain=Xo+Vot+1/2(a*t^2) Xtrain=3.78m +...

Thanks for the help!

projectile is fired w/an angle of 28.0degrees above the horizontal and from height 46.0m agove the ground. the projectile strikes ground w/a speed of 1.95xVo. Find Vo I started using the eqution (Vfy)^2=(Voy)^2+2*Ay*(delta Y) Voy=Vosin(theta)=.47Vo Vfy=1.954*Vosin(theta)=.92Vo...