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  1. T

    Deflection of wave in dissipative media with a complex refractive index

    Homework Statement A monochromatic plane wave with wavelength 500µm is propagating through a dissipative medium with refractive index 1-0.0002i. It approaching the edge of the medium, and will pass out into free space. If the angle of incidence is not 90°, how much will the wave deflect as it...
  2. R

    Masses connected to spring momentum

    Homework Statement An m = 1.3 kg block and an M = 3.0 kg block have a spring compressed between them and rest on a frictionless table. With a stopper in place that prevents m from moving, the spring is compressed and released so that M moves away with a speed 2.0 m/s. The spring is...
  3. R

    Block sliding on top of cart

    Homework Statement A block of mass m =0.75 kg is set on a large cart of mass M = 6.5 kg. The cart's rollers are frictionless, but there is a coefficient of kinetic friction of 0.36 between the cart's surface and the block. The cart is at rest when the block is given an initial speed of 5.2...
  4. K

    Bowl Balanced on a Bowl

    Homework Statement A solid hemisphere of radius b has its flat surface glued to a horizontal table. A second solid hemisphere of different radius a rests on top of the first one so that the curved surfaces are in contact. The surfaces of the hemispheres are rough (meaning that no slipping occurs...
  5. T

    A mass oscillating at the end of a spring

    1. A 250-g object hangs from a spring and oscillates with an amplitude of 5.42 cm. The spring constant is 4.80 N/m. a) What is the acceleration of the object when the displacement is 4.27 cm [down]? I put: m=0.25 kg d=0.0542 m k=48 N/m x=0.0427m Therefore: F=kx which leads to a=kx/m a=(48...
  6. T

    Help Please: Is it possible to make an electromagnet w 2 like ends?

    HELP! Is it possible to create an electromagnet with one continuous wire with 2 like poles (i.e. both ends either north or south)?. Visualising it with the right hand screw rule for current carrying coils, it will be like the picture below, but one end of the coil will be as shown, while the...
  7. N

    Struggling in PDE Class

    I'm a 2nd-semester freshman taking my first upper-level class (partial diff eq) and I'm really struggling. People always ask me what I'm doing in that class as a freshman and I answer by telling them I'm an idiot and a masochist, which is true. I've spent most of my time and energy on that class...
  8. U

    How can I better adjust myself to the American industry?

    Hello, I am a 3rd mechanical engineering major who is heavily interested into going into the nanotechnology field. I chose mechanical engineering because it is a very broad and powerful field. I have heavily interested in nanotechnology and I would love to pursue that field for a career...
  9. T

    A worker lifts a 20.0-kg bucket of concrete from the ground

    Homework Statement A worker lifts a 20.0-kg bucket of concrete from the ground up to the top of a 20.0-m-tall building. The bucket is initially at rest, but is traveling at 4.0 m/s when it reaches the top of the building. What is the minimum amount of work that the worker did in lifting the...
  10. rania yassin

    Jobs in physics

    well,, i still have one and a half year to go,, so you might think that this is a little bit early but this is really a concern for me,, i really don't know what should i do after i graduate,,, I'm majoring in physics and i'm gonna be honest I SUCK AT TEACHING !!! i'm considering having masters...
  11. N

    Is it possible to find the tension force without mass?

    Homework Statement The system to the right has two identical masses. (one is hanging off the ledge of a table, one is on the table, they are connected by a rope.) tge coefficients of kinetic and static friction are .54 and .63 respectively. Find the acceleration and the tension in the rope...
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