physics

posted by .

A square piece of foil with area A = 5.0 × 10^-4 m^2 and mass m = 5.0 × 10^-5 kg is suspended along one edge and hangs under its own weight. When light is incident perpendicular to the foil,the foil bends and reaches an equilibrium angle of 2 degrees. If the light is completely reflected by the foil, what is the peak value of the electric field associated with the light?

  • physics -

    The answer is 62 kV/m.

  • physics -

    I got...

    Torque (by radiation) = F dot R = A*P dot R = A*P cos(theta) R
    P = 0.5 * (electric constant) * E^2

    Torque (by gravity) = -mg sin(theta)

    Torque (by radiation) + Torque (by gravity) = 0

    Then i solved for E. Which gives me a wrong answer. I don't know why.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. physics

    "A one meter board with uniform density, hangs in static equilibrium from a rope with tension T. A weight hangs from the left end of the board 0.2m away in distance. What is the mass of the board"
  2. physics

    a metal wire 1.0 mm in diameter and 2.0 m long hangs vertically with a 5.0 kg mass suspended from it. if the wire stretches 1.2 mm under the tension, what is the value of the young's modulus for metal?
  3. Physics

    An object has a weight of 0.838 N. It is suspended from a scale, which reads 0.705 N when the piece is submerged in water. What are the volume and density of the piece of metal?
  4. Physics

    An object has a weight of 0.852 N. It is suspended from a scale, which reads 0.749 N when the piece is submerged in water. What is the volume of the piece of metal?
  5. physics- Electromagnetic waves

    A square piece of foil with area A = 5.0 × 10^-4 m^2 and mass m = 5.0 × 10^-5 kg is suspended along one edge and hangs under its own weight. When light is incident perpendicular to the foil,the foil bends and reaches an equilibrium …
  6. physics- Electromagnetic waves

    A square piece of foil with area A = 5.0 × 10^-4 m^2 and mass m = 5.0 × 10^-5 kg is suspended along one edge and hangs under its own weight. When light is incident perpendicular to the foil,the foil bends and reaches an equilibrium …
  7. Physics

    A 3.0m long uniform beam of mass 24kg hangs off the edge of a building with 2.5m in the air, as shown in the diagram. A bucket of bolts of mass 30.kg rests on the board over the building at a distance of 10.cm from the edge of the …
  8. physics

    Linearly polarized light is incident on a piece of polarizing material. What is the ratio of the transmitted light intensity to the incident light intensity when the angle between the transmission axis and the incident electric field …
  9. physics

    a metal bar 70cm long and 4.00 kg in mass supported on two knief -edge placed 10 cm from each end. a 6.00 kg weight is suspended at 30 cm from one end . find the reaction at the knife-edge ?
  10. Mathematics

    A cube is divided into six identical square pyramids, each with a perpendicular height (s) that is half the length of the base edge (2s). Show that the volume of each pyramid is one third the volume of a square prism with the same …

More Similar Questions