Recent content by anastasiaw

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    Newton's Laws: Simple Constant Force Problem

    The formula I used to calculate acceleration was: a = (v - v0) / t a is acceleration, v is final velocity (should be 0 m/s), v0 is initial velocity, which you must convert to m/s, t is the time it takes to stop. You can then use the very important equation F = ma to calculate...
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    Calculate Block Friction: 2-kg Block & Horizontal Spring

    Okay I got it -- F(n) is the normal force... the weight of the object. Thanks.
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    Calculate Block Friction: 2-kg Block & Horizontal Spring

    Okay, gravity? How do I apply that to this problem?
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    Calculate Block Friction: 2-kg Block & Horizontal Spring

    Homework Statement A 2- kg block rests against one end of a horizontal spring which is compressed by 18 cm. When the spring is released, the spring forces the block to slide across a table top. It stops 47 cm from where you released it. The spring constant k is equal to 120 N/m. Calculate the...
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    What is the Mass of M1 in a Pulley System with Given Parameters?

    Thanks a lot! This is a big help. I understand it now.
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    What is the Mass of M1 in a Pulley System with Given Parameters?

    Yeah it's 2.056 kg. Can you show me the math for that?
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    What is the Mass of M1 in a Pulley System with Given Parameters?

    Homework Statement M1 and M2 are two masses connected as shown. The pulley is light (massless) and frictionless. Find the mass M1, given that M2 (3.5 kg) accelerates downwards at 3.35 m/s^2, θ is 35o, and μk is 0.25. http://img525.imageshack.us/img525/7076/prob31fricpullplaneyi0.gif...
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    Calculating Minimum Stopping Distance for Truck & Box

    I'm also having trouble with this one if anyone has any advice to offer.
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    Calculating Minimum Stopping Distance for Truck & Box

    Oh simple mistakes... they kill me. I have the right answer now... 104.2 m
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    Calculating Minimum Stopping Distance for Truck & Box

    I'm also having trouble with this problem. Here is what I tried (which didn't work): First my numbers are different. Us=0.25 and v=81.4 km/hr. First I converted 81.4 km/hr to 22.61 m/s. Fs = Us*N => ma = Us*mg => a = Us*g => a = (0.25)(-9.81) = -2.4525 m/s^2 v^2 = v0^2 + 2a(delta x) =>...
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    How Fast Does a Penguin Slide on Ice After 8.75 Seconds?

    Figured it out: for some reason I was thinking "soa" instead of "toa" -- tan of an angle = opposite/adjacent So I should have done arctan (y/x) which yields 32.8 deg; this is the correct answer.
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    Motion & Forces: Speed of Block 5.90s After Start

    A 5.82 kg block located on a horizontal frictionless floor is pulled by a cord that exerts a force F = 12.80 N at an angle θ = 24.0° above the horizontal as shown. What is the speed of the block 5.90 seconds after it starts moving? http://img239.imageshack.us/img239/1153/prob49dj7.gif F = ma...
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    How Fast Does a Penguin Slide on Ice After 8.75 Seconds?

    "Draw the components of the resultant velocity and extract the answer from the right triangle you obtain. The angle must be between 0 and 2 pi radians." That's what it told me when I entered the incorrect answer. I'm taking the x-component of the velocity and the y-component and setting them...
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    How Fast Does a Penguin Slide on Ice After 8.75 Seconds?

    A car that weighs 12000.0 N is initially moving at a speed of 30.0 km/hr when the brakes are applied and the car is brought to a stop in 4.1 s. Find the magnitude of the force that stops the car, assuming it is constant. This is the wrong problem ^^^ A 6.70 kg penguin runs onto a huge...
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    Newton's Laws: Simple Constant Force Problem

    Thanks... :) 17.1 m is the answer.
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