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Hi, I was wondering if someone could help explain how the following shapes would affect convection. What it is is a heat plate with nothing, a bundle of tubes, and just fins. It's in a vertical tube and the air flows upwards. I understand convection but I don't get how it would be affected in...

Homework Statement The following reaction initially contains [A]o = 0.2150 M and [B]o = [C]o = 0.4150 M. If the equilibrium constant for the reaction is Keq = 2.03, what are the concentrations of reactants and products when the reaction has achieved equilibrium? What is the value of deltaG for...

Homework Statement A sealed 1.00 L vessel contains 0.3475 g of argon gas and 6.766 g of an unknown gas at 350 K. If the total pressure of the gas mixture is 2.56 atm, and the unknown gas has an empirical formula of CH2, what is the molecular formula of the unknown gas? Homework Equations I...

1. Consider a rectangular water tank with a length of 8m, a width of 4m , and a height of 5m. Water exits the tank by pouring over the sides. a) If the tank is initially full of water, find the work required to empty the tank. b) If the tank is initially half-full of water, find the work...

I figured out the 2nd one ^^ Just need help with the differentiation one.

I just have two questions: A fundamental problem in crystallography is the determination of the packing fraction of a crystal lattice, which is the fraction of space occupied by the atoms in the lattice, assuming that the atoms are hard spheres. When the lattice contains exactly two...

oh okay. Thanks.

How can I calculate cos ^2 (53)?

It should be e / 1, since the limit is approaching -2, then -1 < x+2 < 1, or x+2 < 1, so delta = 1 and e / 1 ?

Then it'd be delta = e / 0

since it's a value close to -2, can we assume that it is within a distance 1 from -2, that is, -1<x+2<1 , -3 < x < -1 Here's where I was confused: Do I add 1 since the other value was x + 1? so, I'd be -2 < x + 1 < 0 ?or x + 1 < 0 ?

We need to find such a number that restricts x to lie in some interval centered at 2, right?

I get delta = min {1, e/0}

I thought that was enough...where did I go wrong?

I'm supposed to prove that lim x -> -2, x^2+3x+7 = 5 Here's what I have: |x^2 +3x+7 – 5| < ε |x+2| < δ |x^2+3x+2| -> |(x+2)(x+1)| < ε whenever |x+2| < δ |x+1||x+2| < δ |x+1| |x+1||x+2| < δ|x+1| < ε ε / |x+1| > δ , as x -> -2, |x+1| -> 3, therefore: ε / -1 > δ But...

If a circle has an area of t square units and radius r, then a circle with an area of 2t square units has radius 2r.

I'm having trouble with 4 questions and not sure how to go about starting to solve them. If anyone can give me help on how to approach these questions, it'd be really appreciated. I just put them all down at once rather then making separate threads. Thank you. 1) An electrical transmission...

-Use the dot product to prove that the quadrilateral with vertices A(-4,1) B(4,5) C(7,-1) and D(-1,-5) is a rectangle. I tried find AB dot BC = 0, but I'm not getting 0. So I'm stumped. Can someone help me out? =/

Okay, I'll do that. I'll tell you how it goes tomorrow ^^

Actually, that's why I'm here. I told him and he brushed me off, saying F=ma=kx <- Acceleration is constant. I actually just stormed out of the class and had a discussion with the VP about it. I just wanted to make sure I wasn't making a total ass of myself though. Thanks for your help :3

It's a maximum acceleration

Yes, I did too! See, my reasoning is, F=ma=kx, but k and m are constant, therefore when a greater force is applied to scretch the spring (or in this case, compress), acceleration changes (as well as x). However, the other two equations involves a uniform acceleration, which you can't have in...

I used g, yes. and I did convert.

Okay, I'm having a debate with my teacher. He's saying I'm wrong but I still think I'm right. The question is: What should be the spring constant, k, of a spring designed to bring a 1200kg car to rest from a speed of 100km/h so that the occupants undergo a maximum acceleration of 5.0g? He...

We haven't done integrals in this unit so I don't know how to solve that method =(

I did Fg = Gm1m2/r^2 = 1/2mv^2

Hmm I think I rearranged the equation wrong then. Thanks.

I was wondering if someone could tell me if I did this right: Two neutron stars are separated by a distance of 10^10m. They each have a mass of 10^30kg and a radius of 10^5m. They are initially at rest relative to each other. How fast are they moving when they collide? R = 2r + d =...

They would intersect on the midpoint of the hypotenuse, right?

The vertices of a triangle are P(-3,1,2), Q(1,-3,-1) and R(3,-1,-1) -Verify that it is a right angled -Determine the area -Determine the perimeter -What are the coordinates of S(x,y,z) such that PQRS is a rectangle I'm not sure how to start to go about solving this problem. Could...

Two balls A and B having different but unkown masses collide. A is initially at rest and B has a speed v moving North. After collision B has a speed v/2 and moves perpendicular (East) to the original motion. Find the direction of motion of A after collision. Is it possible to determine the speed...

nvm I think you meant 118. if you divided 188, you get 61 degrees.

Wait how did you get -188 for the vertical?

uhmm...thanks for telling me the answer, but it's useless if I don't know how to get the answer =(

I'm supposed to find the equilibriant force on the diagram I posted (see attachments)

Actually, I think I figured it out but are the vertical and horizontal forces correct? Or do the Fh and Fv should cancel out

As you can see in the attachmen, I'm supposed to find the equilibriant force and the force from the left side. So is it something like this: Fx = 0, Fh + 200cos20-100cos30=0 Fh = -101.33N Fy = 0 Fv + 200sin20 + 100sin30 = 0 Fv = -118N But I get stuck on the rest. Can someone...

For the second question, should I resolve the vectors into x and y then use the distances to find sigma t?

I'm having trouble with two problems and I was hoping if someone could point me in the right direction go about solving them: 1) Two beams support a 4.0kg pail of water above an open well. How much compression force is exerted on each beam by the water pail, what outward force do the two...

Just wanted to make sure if I did this right: Two crates of mass 12kg and 20kg are pushed across a smooth floor together, the 20kg crate in front of the 12kg crate. Their acceleration is 1.75m/s^2. What is the action reaction force between the crates? F=ma F=(32)(1.75) F=56N then F...

Okay. Thanks for confirming my answers

Also, for this question: The Easter Bunny runs along a straight and narrow path with a constant speed of 25m/s. He passes a sleeping tortoise, which immediately starts to chase the bunny with a constant acceleration of 3x10^-3m/s^2. How long does it take to catch up to the bunny? I did this...

If Icalculate the wood, do I do the following: v2^2=v1^2 + 2ad 100^2 -400^2 = 2(-750,000)d d=0.1m

I really hope so, because the sheet says "bullet".

a= -750,000m/s^2 F = 6000N Just to save time

A 8.0g bullet traveling at 400m/s passes through a heavy block of wood in 4.0x10^-4s, emerging with a velocity of 100m/s. Ignore the motion of the wood. 1) What is the force exerted by the block on the bullet? 2) What is the force exerted by tbe bullet on the block? 3) How thick is the...

Yes, I used the quotient rule: y'= (1-x^2)(2x)-(-2x)(x^2) / (1-x^2) y'= 2x-2x^3+2x^3 / (1-x^2)

I just wanted to make sure I differentiated this correctly before I started graphing it: y=x^2/1-x^2 y' = (2x)/(1-x^2)^2 y''=(2+6x^2)/(1-x^2)^3

That was a typo on my part (thank you for noticing it!) So there are no minimums in this case? Becaue when I try to calculate it, the 3 critical numbers I get are 2,-2, and 0. But if I sub in 2 or -2, I get 6, which doesn't seem right...

err...it should be maximum, right?