Recent content by shannon.leigh

Are you serious? I just screwed up the calculations? Damn my terrible skills with a calculator! And thankyou thankyou thankyou for pointing that out ehild! I am forever in your debt. :)

Homework Statement 0.5kg of ice at 0 degrees celsius is mixed with 0.1kg of steam at 100 degrees celsius. what will be the final temperature? Homework Equations delta Q= m*c*delta T and at first i thought delta Q= m*Lf ,but then i changed my mind. . . The Attempt at a Solution...

thanks! big help :)

Homework Statement A foundry operator finds that it takes 55.6 MJ of heat to heat a 286 kg mass of an alloy steel from 22 degrees C to 452 degrees C. Specific heat capacity of the steel is 452J/kg/K. If the foundry worker cools the steel by poring water onto it, the water will heat up to its...

Thankyou for that!. . .but I still have one question. . .What's the decay constant? As In how do you calculate it? I think I've been learning by different names. . .

Homework Statement A sample of processed waste from a nuclear reactor contains 1.0*10^24 plutonium-239 atoms. The half life of plutonium-239 is 2.41*10^4 years. a) How many plutonium-239 atoms will decay in the next 2.41*10^4 years? b) Estimate the activity of the original sample...

Sorry 1 and 2 aren't filled in very well but I have absolutely no idea what to do for this question. My brain wasn't designed for physics :( Homework Statement Question: A car traveling at 60.0 km/h has a total retarding force of 1500 N due to air resistance. If 1.00 L of petrol can...

oooohhhhh :) thankyou !

Homework Statement "The initial speed of a stone projected vertically upwards is 21.0m/s a)What is the maximum height it will reach? b) How long does it take to reach the highest point and what is the total time which it is in the air?" Relative information: a=9.8 m/s/s u=21.0...