Physics Answers

Use Kami in completing this activity.

The Sun has a mass of 2.0 x 10 to the power of 30 kg. Its

radius is 7.0 x 10 to the power of 8 meters. The gravitational

force between the sun and a section of the sun's surface is

470 N. What is the mass of this section?

What is the boundary condition for H between two dielectric media (with no free charge and no conduction current)?

Write down the general expression for Poynting’s vector

A plane electromagnetic wave of angular frequency ω and wave number k propagates in a vacuum in the negative x direction. The electric field of the wave is linearly polarised in the y direction. Write down an appropriate expression for the wave electric field.

Please write down Faraday’s Law and Ampere-Maxwell’s equation for time-dependent electromagnetic fields in a medium.

If G one earth is 3kN. How much is m and G on the moon if the gravity there is 1.62m/s²

secutive standing waves occur at frequencies 280 Hz and 315 Hz on a taut

g fixed at both ends. Determine the frequency of the 4th harmonic.

Q1: If a person could not digest food anymore, what would probably happen to that person? Why?

a) the person would gain weight because the undigested food would sit in the person's body.

b) the person would not lose or gain weight, but it would take longer for the body to use the food that was eaten

c) the person would lose weight because most of the food could not be used by the body

d) nothing would change because digestion does not affect the way food is used by the body.

The standing wave on a string is given by the equation y = (0.08 m) sin[120x] cos[150t].

Find

(a) the component waves whose superposition gives this standing wave.

(b) The wavelength and frequency of the standing wave.

(c) The length of the string if 4 nodes and 3 antinodes are formed.

(d) The transverse velocity of the particle of the string at x = 0.04 m and at t = 2 ms.

A standing wave is set up on a string of length L, fixed at both ends. If 6 nodes and 5 antinodes are observed when the wavelength is λ = 2.16 m, then the length of the string is: