# Search results

1. ### Multivariable calculus problem

Homework Statement Find the points on the surface xy^2z^3=2 that are closest to the origin Homework Equations The Attempt at a Solution x,y,z=/= 0, as when x,y,z = 0 it is untrue. Right?? Otherwise, I am very unsure as to how to approach this problem. Should I be taking partial derivatives...
2. ### SHM - Planet Problem

Homework Statement You are exploring a newly discovered planet. The radius of the planet is 7.20 * 107 m. You suspend a lead weight from the lower end of a light string that is 4.00 m long and has mass 0.0280 kg. You measure that it takes 0.0685 s for a transverse pulse to travel from the...
3. ### Differential Equations: Solve the following

Homework Statement Solve the following differential equations/initial value problems: (cosx) y' + (sinx) y = sin2x Homework Equations I've been attempting to use the trig ID sin2x = 2sinxcosx. I am also trying to solve this problem by using p(x)/P(x) and Q(x) The Attempt at a Solution...
4. ### Differential Equations, solve the following: y^(4) - y'' - 2y' +2y = 0

Thank you!! I get it now; gotta work on the algebra XD I've got 99 problems and it's all algebra pretty much.

Thank you!
6. ### Differential Equations, solve the following: y^(4) - y'' - 2y' +2y = 0

Homework Statement Solve the following differential equations/initial value problem: y^(4) - y'' - 2y' +2y = 0 Hint: e^-x sinx is a solution Homework Equations I was attempting to solve this problem by using a characteristic equation. The Attempt at a Solution y'''' -y'' -2y' + 2y = 0 -->...
7. ### Chemistry: Heat of Sublimation and Hydrogem Bonds Problem

of the reaction H20 (g) + HOH (g) -> H2O --- HOH (in ice)
8. ### Chemistry: Heat of Sublimation and Hydrogem Bonds Problem

I believe it's -21 kJ/mol
9. ### Chemistry: Heat of Sublimation and Hydrogem Bonds Problem

Homework Statement Using the heats of fusion and vaporization for water, calculate the change in enthalpy for the sublimation of water: H2O(s) --> H2O(g Using the delta H value given in Exercise 24 and the number of hydrogen bonds formed to each water molecule, estimate what portion of the...
10. ### Electrical Force Problem

OH! Thank you so much. I got the right answer. A proton is q = +1.6 x 10-19 C. Now I know that for in the future.
11. ### Electrical Force Problem

Homework Statement An alpha particle (charge equals +2e) is sent at high speed toward a gold nucleus (charge equals +79e). What is the electrical force acting on the alpha particle when it is (2.0 x 10-14) m from the gold nucleus? Homework Equations I tried using Coulomb's law, which is E =...

13. ### Rollercoasters and Loops and Normal Forces

Homework Statement <I will attach a diagram below> In terms of m, g and r. FInd the normal force at the top of the loop. Homework Equations ∑F = Fc = FN+Fg ∴ Fc=FN+Fg ∴FN = Fc - Fg ∴ N=mV2/r - mg The Attempt at a Solution Fc=mV2/r - mg and V2=ra and a=g ∴C=mrg/r ∴C = mg ∴mg-mg=N ∴ N=0 N. BUT...
14. ### Elastic Collision on a Frictionless Track

The top is the image that goes with the problem. Below is my work.
15. ### Elastic Collision on a Frictionless Track

Homework Statement Consider a frictionless track as shown (I will attach an image in a follow up post). A block of mass M1= 5.00 kg is released from point A. It makes a head-on elastic collision at B with a block of mass m2 = 10 kg that is initially at rest. Calculate the maximum height to...
16. ### A Power Problem

Okay! I'll try that out.
17. ### A Power Problem

Okay here is my work!! The problem I solved for was #48 and my answer is 700 Watts?

Okay got it.
19. ### A Power Problem

35 comes from my sine calculation for the height of the slope. I will reloik at the problem about the tension, thanks!
20. ### Help with Forces, Pulleys, and Whether People get pulled

Yes we are supposed to use ten; my teacher doesn't really care about sig figs though.

My attempt!!
22. ### A Power Problem

Homework Statement A skier of mass 70 kg is pulled up a slope by a motor-drive cable. a. How much work is required to pull him 60 m up a 30° slope (assumed frictionless) at a constant speed of 2 m/s? b. What power must a motor have to perform this task? Help would be greatly appreciated...
23. ### Help with Forces, Pulleys, and Whether People get pulled

Okay yay!! Thanks for the help. Its nice to finally understand it.
24. ### Help with Forces, Pulleys, and Whether People get pulled

This is my solution for part C. Is it correct?
25. ### Help with Forces, Pulleys, and Whether People get pulled

Yes, 11.42 is my answer, but I will take another look.
26. ### Help with Forces, Pulleys, and Whether People get pulled

Does this look okay?
27. ### Help with Forces, Pulleys, and Whether People get pulled

!! Since he is climbing the force he is applying will be in the opposite direction of his motion, and that will make tension larger?
28. ### Help with Forces and Pulleys

!! Thank you! I misread my formula sheet (again) omo.
29. ### Help with Forces and Pulleys

Oh darn, I'll take a look at that. @wrongedMan some pics would help a ton!! Thank you for the help @haruspex as well
30. ### Help with Forces, Pulleys, and Whether People get pulled

T this is my attempt at part A and below is my image