Recent content by Phyzix

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    Optimizing Boat Direction in a River with Current: A Vector Diagram Approach

    ahh thanks! I was thinking along these lines but I couldn't decide if the hypotenuse was the 10 or one of the legs..thanks a lot guys :) :biggrin:
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    Optimizing Boat Direction in a River with Current: A Vector Diagram Approach

    I know i need to use a simple vector diagram ...but I'm not sure how to set it up... In what direction should a boat point if it has a speed of 10 m/s, and wants to end up directly across a river with a current of 5 m/s. help? :confused: :bugeye: :rolleyes:
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    Comparing Forces and Power in a Pulley System: Help with Multiple Choice

    Help please--multiple choice Two identical blocks are lifted at constant velocity by ropes that run over frictionless pulleys, as shown in the diagram. Block B is raised twice as fast as Block A. The magnitudes of the forces are respectively FA and FB, while the power supplied is respectively...
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    What Happens When a Fast-Moving Cube Collides with a Stationary Ball on a Table?

    10) A 5 kg ball sits motionless at the edge of a 2m long 1.2m tall table. A cube of mass 0.5kg plows into it head-on at a speed of 26m/s There is a graph below in the attachments about the collision. a) Determine the total impulse given to the ball. b) Determine the velocity of the...
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    Perfectly elastic collisions (proof)

    An object collides elastically (perfectly) with another object (identical object) at rest. If it is not a head on collision how can i PROVE that the angle between them afterwards is 90 degrees? :confused: :bugeye: I have NO IDEA on what to do...it's been puzzling me and my friends for a...
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    Solving Coefficient of Static Friction for Friction Problem & Grass-Skiing

    A Man dragged a 51 Kg bag at a 45 degree angle with a force of 400 N. The bag moved along hte pavement with a constant speed. What is the coefficient of static friction? OK SO, you can make a triangle and figure out that 283 N are pulling horrizontal and 283 pulling vertically. But I am not...
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    How Do You Solve Rocket and Escalator Motion Problems?

    Thanks, I think that I understood that really well...but a similar question is: A spaceship is observed traveling in positive x direction with a speed of 150 m/s when it begins accelerating at a constant rate. The spaceship is observed 25 s later traveling with an instantaneous velocity of...
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    How Do You Solve Rocket and Escalator Motion Problems?

    the acceleration in problem 1 is the acceleration during the period of time when the rocket is on--not when it has been turned off... btw, thanks a lot for the help with the other one but t=S/(V1+V2)...where did you get 1 for S...did you just use it as 1 unit? and why does the t become 1/t?
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    How Do You Solve Rocket and Escalator Motion Problems?

    OK---a rocket is launched at 53 degrees above horizontal with an initial speed of 100 m/s. It moves along its initial straight line path with an acceleraqtion of 30 m/s^2 for 3 seconds. At this time, the rocket is turned off and it proceeds to fall as a free body. how can i find,A) the...
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    How can I calculate the time it takes to walk up a working escalator?

    OK---a rocket is launched at 53 degrees above horizontal with an initial speed of 100 m/s. It moves along its initial straight line path with an acceleraqtion of 30 m/s^2 for 3 seconds. At this time, the rocket is turned off and it proceeds to fall as a free body. how can i find,A) the...
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