Recent content by rubenhero

thank you, that makes sense now. the radius is 5 so it would be (1/2)∏52.

thank you for your quick response, is y=\sqrt{1-x^2} a circle?, oh a circle isn't continuous so i can't do antiderivatives? i have learned substitutions but if i let u be 25-x2, du = -2x dx, i would have to put a (-1/2x) in front of the integral, then integrate u to be (2/3)u3/2, wouldn't i...

Homework Statement Find the exact value of: ∫-55 √25-x2 dx without using your calculator. (Hint: Consider the geometric significance of the definite integral.) Homework Equations integrate and find antiderivative and evaluate at A and B. The Attempt at a Solution ∫-55 √25-x2 dx...

thank you for your reply so would the whole proof be 1.A ∩ (A ∪ B) is a subset of A x is a element in A ∩ (A ∪ B) x is a element in A by definition of intersection Therefore A ∩ (A ∪ B) is a subset of A 2.A is a subset of A ∩ (A ∪ B) x is a element in A x is a element in...

Homework Statement Prove the second absorption law from Table 1 by showing that if A and B are sets, then A ∩ (A ∪ B) = A. Homework Equations Absorption laws A ∪ (A ∩ B) = A A ∩ (A ∪ B) = A The Attempt at a Solution i will show A ∩ (A ∪ B) is a subset of A x is any element in A...

Thanks you for responding. You were right, I just did the sum of the entropy loss and gain and got an answer of .5629265733 J/K. Webassign marked my answer as right. Thanks again for your help!

Homework Statement b) The temperature inside a house is Tin = 19.2° C when the temperature outside is Tout = 10.7° C. If Q = 5.49 kJ of heat leak from the house to the outside, find the change in entropy caused by this process. Homework Equations W = QH - QC, dS = dQ/T The Attempt...

Thank you ehild, I redid all the work and got the correct answers.

Homework Statement An engine operates with n = 1.94 moles of a monatomic ideal gas as its working substance, starting at volume VA = 21.4 L and pressure PA = 2.77 atm. The cycle consists of: - A to B: an isobaric expansion until its volume is VB = 50.1 L - B to C: an isochoric (constant...

Thank you grzz and mtayab1994 for responding. It would be easier if the problem did provide n to use PV = nRT. I am confused, should I be using .008 kg for the mass because helium gas has 2 atoms?

Homework Statement c) Find T, the temperature at which He gas molecules have an rms speed of v = 733 m/s. Homework Equations Vrms = √(3kT/m) The Attempt at a Solution (Vrms2m)/3k = T (7332*.004kg)/(3*1.381e-23J/k) = T 5.187e25k = T Any help with figuring out what I did wrong...

Homework Statement What is the difference between molecular mass and molar mass? Are they related? Homework Equations moles = total mass/ mass/mole The Attempt at a Solution I can't find any explanation in my lecture notes. I think that: molecular mass = mass of one molecule...

Thank you phyzguy and SammyS for responding. After taking into account about what you said, I realized that the 32s cancel themselves and ended up only needing to take 5/9 of 13.7. I got an answer of 7.61 Celsius degrees. Is this the correct?

Homework Statement a) One day, the temperature outside changed by 13.7 degrees on a Fahrenheit thermometer. By how much did the temperature change on a Celsius thermometer? Homework Equations F = (9/5)C + 32 The Attempt at a Solution F2 - F1 = 13.7 (9/5)C2 + 32 -(9/5)C1 + 32 = 13.7...

Thank you for your help ehild, that "ASSUME: The balloon material displaces a negligible amount of air, and therefore creates no measurable buoyancy. " part really confused me. I accounted for the mass of the balloon material and got an answer to be 590585.5565Pa, I put in 5.90e5Pa and it is the...