Recent content by premed

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    Sn1 vs. Sn2 Mechanisms. Strong or Weak Nucleophiles?

    One can predict by which mechanism a reaction will occur, Sn2 or Sn1, by the substrate's order( i.e. primary, secondary, or tertiary carbon) and by the strength of the nucleophile. How can I tell if a nucleophile is strong or weak? For instance, one problem showed methanol combining with...
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    What is the condition for destructive interference in thin films?

    Sorry. I'll clarify. The book gives the equation for constructice interfence as 2T=m\lambda where m is an integer. For destructice interference 2T = (m+1/2)\lambda . that's why i put in 2T = \lambda /2. The m in this case doesn't matter as long as 2T is not an integral multiple of \lambda...
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    What is the condition for destructive interference in thin films?

    Homework Statement Light of wavelength \lambda strikes a pane of glass of thickness T and refractice index n, as shown in figure(I attached a diagram I made). Part of the beam is reflected off the upper surface of the glass, and part is transmitted and then reflected off the lower surface of...
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    Helpppp EM Radiation doesn't make sense to me

    awwww ok i get it. its momentum is first positive going towards the surface then negative when leaving the surface, which means its magnitude of change is 2x rather than x. Thanks a lot.
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    Helpppp EM Radiation doesn't make sense to me

    But i don't understand WHY it exerts pressure twice when it reflects. If a photon hits an object, doesn't it only exert pressure as it bounces off? Isn't the enitre collision only one instant? Tell me if this analogy works because it kinda helps me to understand but I'm not sure if it is...
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    How Is the Formula for Radiation Pressure on a Reflecting Surface Derived?

    for a reflecting surface, the radiation pressure is equal to 2I/c where I is the intensity of light and c is the speed of light. I saw this in my physics homework manual but it was never mentioned in the book. thanks.
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    Helpppp EM Radiation doesn't make sense to me

    Helpppp please. EM Radiation doesn't make sense to me Hi. I don't see how you would get the answers to these questions. 1) A beam of light is shone on two sheets of paper, one of which is perfectly absorbing black and the other perfectly reflecting white. If the radiation pressure on the...
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    How Can I Solve These Physics Problems on Forces and Tensions?

    ya that sounds right. I never thought to add the masses. I kept trying to solve for different parts in f=ma seperately for each block. Thanks a lot. Now I am trying to solve the second problem. I trying to figure out if the Y component of the tension is the sum of the two hanging weights or if...
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    How Can I Solve These Physics Problems on Forces and Tensions?

    hey could someone please reply. I'm not getting anywhere with these problems
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    How Can I Solve These Physics Problems on Forces and Tensions?

    Help please. Need help with these problems. Hey. I'm really not good at physics and my professor only tells stories all day so I need help with these problems. Please be as descriptive as you can so I could understand the solution. 1) A woman pushes two crates across a frictionless horizontal...
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