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    Friction involving cylinder

    Homework Statement see attachment Homework Equations see attachment The Attempt at a Solution I understand everything about the problem except how to determine the angle P makes with the new horizontal axis (parallel with F)--see diagram under primary one... so that I can sum the...
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    Analysis of structures

    I have a question on setting up a problem to find the reactions and forces in members of trusses. So initially I find the reactions at the pins using a free body diagram, I get that. However, when I need to find the forces of the particular members am I supposed to take an initial guess as...
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    Did I get this right? (collision in 2-d)

    So it should have been 30 m/s instead of the 26 that I wrote? :(
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    Did I get this right? (collision in 2-d)

    Homework Statement 2 birds of same mass swoop down on a mouse at an angle of 60 deg from horizontal with speed 30 m/s. They collide and stick together, what is their resultant speed? Homework Equations Conservation of momentum. The Attempt at a Solution This was just on a test...
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    Final speed after dragging crate

    Homework Statement A 96 kg crate, starting from rest, is pulled across a floor with a constant horizontal force of 350 N. For the first 15m the floor is frictionless and for the next 15 m the coefficient of friction is .25. What is the final speed of the crate? Homework Equations...
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    Is the textbook wrong or am I?

    So you're saying you got the book's answer? I used the conservation of energy subbing values for spring and taking into account y=0 when crossing the original spring length. I'm quite sure I have the right answer and the book's is wrong but I just want to verify.
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    Is the textbook wrong or am I?

    Homework Statement A vertical spring (ignore its mass), whose spring constant is 875 N/m is attached to a table and is compressed down by .160 m. (a) What upward speed can it give to a .380 kg ball when released? Homework Equations Conservation of Energy using 1/2 k x^2 for...
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    Apparent Weight in Space

    Disregard.. Figured it out.
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    Apparent Weight in Space

    Homework Statement What is the apparent weight of a 75 kg astronaut 2500 km from the center of the Moon in a space vehicle (a) moving at constant velocity and (b) accelerating towards the moon at 2.3 m/s^2. State direction in each case. Homework Equations F=Gm1m2/r^2 and F=mg The...
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    Work done in relation to angle

    doh. I knew that. It's late here :) What I meant was that I was given two work problems. Both give mass of object, both give h, one gives angle and the other does not. But from what I see the work is calculable on both of them. However, the angle is necessary to use in the problem where it...
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    Relearning Physics

    I am currently in University Physics I. I get the ideas but I'm not where I want to be overall in the class. It takes me way too long to grasp the concepts and then apply them. My Prof is a first year Prof and every student complains about his teaching, i.e. it sucks. In addition to this I...
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    Work done in relation to angle

    Homework Statement Work pushing car up incline. More of a generalization than anything. Is the work done independent of the angle of the hill seeing as all we're concerned with is the change in h? I had two problems on the homework. One carrying a backpack up a hill where the angle wasn't...
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    Mass change in elevator

    Homework Statement Normal mass is 65kg. I get into an elevator, on a scale in the elevator and it reads 76 kg. Find a along with direction. Homework Equations w = mg + ma The Attempt at a Solution Obviously the elevator is accelerating upwards due to the apparent increase in mass...