Recent content by evan4888

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    Electromagnetic waves - antennas

    I will need a little more guidance than that. I am thinking that I need to find the emf, but I am not sure how I could do that without a variable of time. Or would I just use the equation: \varepsilon_m = N \omega A B
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    Electromagnetic waves - antennas

    I just need a little direction to get started on this problem. A magnetic dipole is uded to detect an electromagnetic wave. The antenna is a coil of 50 turns with radius 5.0 cm. The EM wave has frequency 870 kHz, electric field amplitude 0.50 V/m, and magnetic field amplitude 1.7 x 10^-9...
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    Solve Integral: \int^2_1 \frac{dx}{(3-5x)^2}

    Here is the problem: \int ^2_1 \frac{dx}{(3-5x)^2} u = 3-5x du = -5dx dx = -\frac{1}{5} du so, (with the 7 and 2 being negatives) = -\frac{1}{5} \int^7_2 \frac{du}{u^2} = -\frac{1}{5} (-\frac{1}{u})]^7_2 But what I don't understand is how the u^2 becomes...
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    Differerntiating Exponential Functions

    Is this even close to the right answer? Or do I need to also multiply by the derivative of the exponent? ( \ln x )^\cos x ( \ln ( \ln x) )
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    Differerntiating Exponential Functions

    I really really need help with this one. This was a bonus question for one of my previous exams. I have no idea how to work through it. Differentiate the function: y= ( \ln x ) ^\cos x
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    Calculating Speed After Collision in Railroad Freight Yard

    In the railroad freight yard, an empty freight car of mass m rolls along a straight level track at 1.0 m/s and collides with an initially stationary, fully loaded boxcar of mass 3.8m. The two cars couple together upon collision. (a) What is the speed of the two cars after the collision...
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    How Far Does the Block Travel After a Bullet Collision?

    this helps a whole lot. Thank You! But what does the s in the final equation represent?
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    How Far Does the Block Travel After a Bullet Collision?

    A 0.010-kg bullet traveling horizontally at 400.0 m/s strikes a 4.0-kg block of wood sitting at the edge of a table. The bullet is lodged into the wood. If the table height is 1.2 m, how far from the table does the block hit the floor? this is what i did: lets the mass of bullet = m2 the...
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    Work Done on Sled by Rope: 5.0s, 250N, 470N

    A sled is dragged along a horizontal path at a constant speed of 1.5 m/s by a rope that is inclined at an angle of 30 degrees with respect to the horizontal. The total weight of the sled is 470 N. The tension in the rope is 250 N. How much work is done by the rope on the sled in a time...
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    Minimum Angular Speed for Safe Ride on ROTOR

    I think I know how to find the max cetripetal acceleration with ac = v2/r or v = sq. root of r(ac). But without knowing the weight of the people inside the ride, I just don't understand how you would find the minimum angular speed.
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    Minimum Angular Speed for Safe Ride on ROTOR

    The ROTOR is an amusement park ride where people stand against the inside of a cylinder. Once the cylinder is spinning fast enough, the floor drops out. If the coefficient of friction is 0.42 and the cylinder has a radius of 2.5m, what is the minimum angular speed of the cylinder so that the...
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