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  1. H

    Please check my derivative if its correct

    Homework Statement find a formula for the derivative of the function y = f(x) that satisfies the equation below. Homework Equations \frac{1}{x^{2}+y^{2}}\ = 2xy The Attempt at a Solution so my final answer is 2x4f(x)+4x2f(x)2+2f(x)3 all over -2f(x)-2x5-4x3f(x)-2xf(x)2 Am i doing it...
  2. H

    Area, volume and depth relation?

    im not given any dimensions. All i get in the question is the orifice area and that it collects certain volume of rain water over a period of time.
  3. H

    Area, volume and depth relation?

    Area, volume and depth relation? Im given a object, which is a rainguage orifice. it has an area of a certain value. This object collects x amount of water. How do i find a depth from these given values? Is there a formula for calculating depth?
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    Question about chromate-dichromate equilibrium?

    Ok so when i add HCl to a chromate solution, it turns orange (dichromate) because the equilibrium shifts to the right, inorder to reduce the excess hydrogen ions from the HCl Acid. But when I add HCl to dichromate, the color changes the same. How do i explain this phenomenon. and is this...
  5. H

    How do you graph this?

    so the graph shouldnt look any different from regular time vs concentration?
  6. H

    How do you graph this?

    In chemistry Im suppose to graph reciprocal of time ( seconds ) Vs concentration of a solution. Im suppose to plot 3 different plots, which i have obtained from the lab we did. So i have 3 different concentration each with different time. its not reciprocal of time vs reciprocal of...
  7. H

    Calculate heat lost or gained?

    0.100 mol/L + 23 ml of Potassium Hydroxide is mixed with 18 ml of hydrobromic acid. Calculate the heat gained or lost by the reaction. The initial temperature was 20.1 celcius and the final was 24.5 celcius. i have no clue how to solve this equation. Can someone give me clues and what...
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    Chemistry Gas problem

    A gas collecting tube full of water is inverted in a beaker of water in which a reaction is taking place. The water level in the tube is at 200.0 ml at the beginning of the experiment, and at 125.0 ml, at the end. the pressures is 750.0 mm Hg and the temperature is 85.0 Celsius. Calculate the...
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    Electron and parallel plate question >

    electron and parallel plate question >:( Homework Statement The diagram below shows an electron entering the region between the parallel plates of a cathode ray tube. The electron has an initial velocity of 4.8x10^7 m/s horizontally and enters the exact middle point between the plates. The...
  10. H

    Equation of tangent questions

    sorry. I was referring to the slope from point A to point (2 , 4)
  11. H

    Equation of tangent questions

    I dont understand why the tangent slope is equal to the regular slope.
  12. H

    Equation of tangent questions

    Homework Statement Given the function y = x^{2} + 3x - 4 find, a) the equation of tangent + normal at x = -2. b)the equation of the tangent that has slope of -2. c)local min and max. d)the equations of the tangent from the point (2 , -4) to the curve. e) area enclosed by the tangent at...
  13. H

    Log application question

    I'm having trouble with this question. The percent "P", of caffeine remaining in your bloodstream is related to the elapsed time, "t', in hours, by t = 5(log P/ log 0.5) a) How long will it take for the amount of caffeine to drop to 25% of the amount consumed? b) Suppose you drink a cup...
  14. H

    Forgot how to graph sin graphs(translation)

    Ok so i have a function cos4/3x between 0<= X <= 2π the amp is 1, max is 1 and min is -1. the period is 3π/2. normally in a cos graph, π/2=0, π=-1, 3π/2=0 and 2π=1. but since the period is 3π/2, i know the 1 is now at 3π/2. But Im getting confused as to where the 0s and the negative -1 would...
  15. H

    Quick trig identity question

    Does CSC(\pi/2 - x) = SinX OR 1 / SinX? What about CSC2(\pi/2 -x)? Does COT(\pi/2 + x) = -TanX or 1/-TanX?
  16. H

    Elastic collison of 2 moving object

    a .900 kg object is moving east at 2.8 m/s. a 1.30 kg object is moving west at 1.4 m/s. If the collision is perfectly elastic find the velocities after the collision. (neglect friction) I know momentum and kinetic energy is conserved but Im really clueless as to what to do. Please help me...
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    Question abot solving final velocity in elastic collision

    A 0.25 kg ball is attached to a 26-cm piece of string. The ball is first raised so that the string is taut and horizontal, then the ball is released so that, at the bottom of its swing, it undergoes an elastic headon collision with a 0.21 -kg ball that is free to roll along a horizontal table...
  18. H

    Conservation momentum in 2D

    ok i got like 2.26 m/s just before the collision. i know that in perfectly elastic collision, the kinetic energy is conserved. so my energy statement would be something like this Ek initial = Ek ball1 + Ek ball2. right? but when i expand and plug in the givens, Im left with 2 unknowns...
  19. H

    Conservation momentum in 2D

    i seem to having trouble with questions related to elastic collisions. Please help me out if you can please. A 0.25 kg ball is attached to a 26-cm piece of string. The ball is first raised so that the string is taut and horizontal, then the ball is released so that, at the bottom of its...
  20. H

    Elastic Energy and Conservation of Energy

    Homework Statement A horizontal spring of force constant 12 N/m, is mounted at the edge of a lab bench to shoot marbles at targets on the floor 93.0cm below. A marble of mass 8.3 x 10^-3 kg is shot from the spring, which is initially compressed a distance of 4.0 cm. how far does the marble...
  21. H

    Please help me understand relationship between work and friction/gravity

    can you explain why the friction force can be positive? And yea i meant to say something moving vertically downwards. But curious, how can something free falling move vertically upwards?
  22. H

    Please help me understand relationship between work and friction/gravity

    Homework Statement Can the work done by the force of kinetic friction on an object ever be positive? If "yes" give and example. If "no", explain why not. I've said it can never be positive because the force of friction is always opposite in direction of the displacement the second question is...
  23. H

    How to solve planet orbital question

    i asked my friend how he had solved it, and he said he used Fc=FG 4pi^2mr/T^2 = Gm1m2/r^2 does my method and his method work in this question?
  24. H

    How to solve planet orbital question

    Ok I remeber a question on my physics test. where theres a planet orbiting a star in some other solar system. heres what was given to me. the radius,and the time it took for it to finish 1 revolution. I was asked to find the mass of the sun, that the planet was orbiting around so heres what i...
  25. H

    Planet orbital period question

    ummm... whats that? Ive never learned that.
  26. H

    Planet orbital period question

    Mars travels in a nearly circular orbit of radius 2.28 x 10^11 m around the Sun. The mass o Mars is 6.27 x 10^23 kg. The gravitational force of attraction between mars and the sun has a magnitude of 1.63 x 10^21 N. a) what is the speed of Mars? i got 2.4 x 10^4 m/s b)Determine the period...
  27. H

    Centripetal acceleration

    You are whirling a rubber stopper of mass something attached to a string in a vertical circle at high constant speed. At the bottom of the circle, the net force that causes acceleration is my answer was Vertically upward and greater in magnitude than MG. but the answer in the book says...
  28. H

    Uniform circular motion equation

    I dont understand :-(
  29. H

    Uniform circular motion equation

    ok so we did a lab. By looking at the graph, we determined that force of tension is proportional to frequency of revolution radius is indirectly proportional to the frequency of revolution mass is indirectly proportional to the frequency of revolution the next part of the question is...
  30. H

    I have no clue what the normal force is :-(

    An adult is pulling two small children in sleigh over level snow. The sleigh and the children have a total mass of 47 kg. The sleigh rope makes an angle of 23 with the horizontal, The coefficient of kinetic friction between the sleigh and the snow is 0.11. Calculate the magnitude of the tension...