Posts by Anna
Total # Posts: 2,659
Assumed that north is the y-direction and east the x-direction. You are piloting the boat that moves at a constant speed of 10 km/hr relative to the water beneath it. 1) On a body of still water, you point your boat due north for 2hr, then turn due east and continue for ...
March 8, 2016
A projectile is launched from ground level at an angle of 45 degrees above the horizontal with a speed of 40m/s. It is aimed straight towards a high wall that is a horizontal distance of 120m away from the launch point. a) How much time will the projectile spend in the air ...
March 8, 2016
A solid disk rotates in the horizontal plane at an angular velocity of 0.0684 rad/s with respect to an axis perpendicular to the disk at its center. The moment of inertia of the disk is 0.190 kg·m2. From above, sand is dropped straight down onto this rotating disk, so ...
March 3, 2016
exercise 5.8 write an informal proof of Premises: LeftOf(a,b) | RightOf(a,b) BackOf(a,b) | ~Leftof(a,b) FrontOf(b,a) | ~RightOf(a,b) SameCol(c,a) & SameRow(c,b) conclusion BackOf(a,b) State if you use proof by cases.
February 22, 2016
Math please help urgent!!
2. If m<1=43, what is m <4? 53 43****** 37 27 3. If m <1=43, what is m <5? 50**** 40 35 25 <=the angle sign Unfortunately i can not link the graph. But it is horizontal and a vertical crossing line then a diagonal line drawn through each right angle mke by the ...
February 18, 2016
What release height would be required for a 5 micrometer spherical spore to drift from africa to south america (distance =3200km)? assume spore density is 1.2. assume steady 6m/sec horizontal wind from africa to s.america.
February 16, 2016
Chaz is a college student. He has a checking out balance of -$52.00. His roommate Will's checking out balance is -$59.25. Chaz thinks that Will owes more to the bank than Chaz does. Is Chaz correct?
February 12, 2016
Is it possible to separate Bi, Cu and Ag from a mixture containing: c(BiO+)=0,08M c(Cu2+)=0,242M c(Ag)=0,106M c(HClO4)=1M Eo Bi = 0,32 V, Eo Cu = 0,337 V, Eo = 0,792 V _______________ Using Nernst equation (E=E°-0,0592/n -logQ) i see it's possible to separate Ag, but ...
January 20, 2016
a trolley of mass 200kg is travelling north at 2m\s. It collides head on with a second trolley of mass 500kg which is travelling south with a velocity of 5 m\s and they remain coupled together. a)calculate the velocity of the two trolleys after collision. b)what is the ...
January 18, 2016
WOW, juice. Apparently you don't have a sense of humor, or know how to take a joke. We all know its the teacher job to grade the students mind, not their paper. But that's not the way things work. Honestly, your just being a hater, your taking a look at a situation you...
January 14, 2016
Calculate pH and concentration of H2SO3, H2SO3- and SO32- in NaHSO3 c=0,05M. Ka1= 1,23*10^(-2) Ka2= 6,6*10^(-8) Results attached are: a) [H2SO3]= 1,04x10-4 M, [SO32-]=1,3x10-4 M, [HSO3-]= 0,05 M but i keep getting different numbers.
January 7, 2016
Enter the formulae of the products and give their states. Type your answer using the format Na2SO4(aq) for Na2SO4(aq). Do not balance the equation. If there are no products, enter "none". ZnCO3(s) + heat ---> I know it's a decomposition reaction, so I thought ...
December 24, 2015
An object of mass m attached to a spring of force constant k oscillates with simple harmonic motion. The maximum displacement from equilibrium is A and the total mechanical energy of the system is E. What is the object's velocity when its potential energy is 2/3E? the ...
December 15, 2015
A large screen at a theater measures 65 feet diagonally. The aspect ratio (width compared to height) of the screen is 21:9. What is the approximate width and height of the screen?
December 6, 2015
A horizontal water pipe goes from a large diameter to a small diameter and then back to the first diameter as shown in the figure below. The level of water (8cm in the larger tube and 4 cm in the constricted tube) in the small vertical tubes provides us with information about ...
December 4, 2015
Please answer ! Answer everything! A right rectangular prism is intersected by a horizontal plane and a vertical plane. The cross section formed by the horizontal plane and the prism is a rectangle with dimensions 8 inches and 12 inches. The cross section formed by the ...
December 3, 2015
For a short distance , an elephant can run about 24 9/10 miles per hour. A human can run about 27.89 miles per hour over the same distance . How much faster does a human run that an elephant ?
December 1, 2015
To meke a batch of sugar cookies , you need 0.75 cup of sugar and 1/3 cup of butter , among other ingredients. How much more sugar do you need that butter? a) 5/12 cup b) 3/4 cup c) 1/2 cup d) 2/3 cup
December 1, 2015
in one smowstorm there was 3 2/5 inches of snow ,on the ground. In a second strom, 5.65 inches were added to what was already on the ground . How much total snow was on the ground if none melted between storms? a) 2.25 in b) 9.05 in c) 1.66 in d) 5.21 in
December 1, 2015
Two objects of different masses are joined by a light rod. a) Id the moment of inertia about the center of mas the minimum or maximum and why? b) If the two masses are 3kg and 5kg and the length of the rod is 2m, what are the moments of inertia of the system about an axis ...
November 22, 2015
Biology Check answers
1. Which of the following correctly describes the image below? ￼ protein Molecule RNA Molecule amino Acid carboxylic Acid 2. Glucose and fructose are monosaccharides that have the same chemical formula, C6H12O6. However, they do not react...
November 20, 2015
anyone know how to do this and which choice is correct?thank you so much in advance. Use the Henderson-Hasselbalch equation to calculate the pH of a buffer that is 0.350 M acetic acid and 0.250 M sodium acetate. a.4.89 b.4.47 c.4.59 d.none of the above is is not 4.74
November 17, 2015
can some one help me with a few chem questions please. A chunk of iron weighs 4.32 g. a) How many iron atoms are there in this sample? 55.85 g Fe = 1.00 mol Fe = 6.022 x 1023 atoms Fe b) How many moles of iron are there in this sample? 2. . You have a copper bar weighing 71.24...
November 12, 2015
Which of the following processes releases energy to be used by a cell? a phosphate group is added to ATP to form ADP. a phosphate group is removed from ADP to form ATP. a phosphate group is added to ADP to form ATP. a phosphate group is removed from ATP to form ADP. not sure ...
November 9, 2015
A large box has a mass of 500kg and the coefficient of static friction for the box and the floor is 0.45, and the coefficient of kinetic friction is 0.30. a. What is the minimum horizontal force needed to get the box moving? b. If you continue to push with that force, what ...
November 8, 2015
A mystery surprise box is sliding down a ramp at a constant speed. The box has a mass of 55.0kg and the ramp makes a 40.0 angle with the horizontal. What is the coefficient of kinetic friction between the box and the ramp? Please help asap. Thank you.
November 8, 2015
I personally think it's a because art has many different subjects as I've learned in my art class as I've gone through each lesson with art related to math or social studies so I think it is most likely A ;)
November 5, 2015
That's the problem. I was able to get the second part but cannot figure out the top. I have (P + 2.6688)(4.5 - 0.13356) = 144.453 4.366 P - 11.653 = 144.453 P = 35.755 atm but that isn't right.
October 23, 2015
Use the van der Waals equation of state to calculate the pressure of 3.60 mol of NH3 at 489 K in a 4.50-L vessel. Van der Waals constants can be found here. P= Use the ideal gas equation to calculate the pressure under the same conditions. P= I have tried absolutely everything...
October 23, 2015