Question One (a) What is resonance? Give any two examples of resonance.
(b) Define the following terms as they relate to sound (i) Pitch (ii) Intensity and (iii) Loudness
(c) Calculate the frequency of the 3rd normal mode of a guitar string of length 40.0cm and mass
0.5g when stretched with a tension of 80N.
Question Two
(a) An eighteen gauge copper wire has a nominal diameter of 1.02mm. This wire carries a
constant cuirent of 1.67A to a 200w lamp. The density of free electrons is 8.5 x 1028 electrons
per cubic metre. Find the magnitude of:
i.
The cuirent density
The drift velocity
ii.
I
(b) A 1800w toaster, a 1.3KW electric frying pan, and a 100w lamp are plugged to the same
20A. 120V circuit.
i.
What current is drawn by each device and what is the resistance of each device?
State whether this combination will blow the fuse or not.

You throw a small rock straight up from the edge of a highway bridge that crosses a river. the rock passes you on its way down, 7.00 s after it was thrown. what is the speed of the rock just before it reaches the water 28.0 m below the point where the rock left your hand? ignore air resistance.

To understand the electric potential and electric field of a point charge in three dimensions consider a positive point charge q, located at the origin of three-dimensional space. throughout this problem, use k in place of 14? ? 0. part adue to symmetry, the electric field of a point charge at the origin must point from the origin.answer in one word.part bfind e(r), the magnitude of the electric field at distance r from the point charge q.express your answer in terms of r, k, and q. part cfind v(r), the electric potential at distance rfrom the point charge q.express your answer in terms of r, k, and q part dwhich of the following is the correct relationship between the magnitude of a radial electric field and its associated electric potential ? more than one answer may be correct for the particular case of a point charge at the origin, but you should choose the correct general relationship. a)e(r)=dv(r)drb)e(r)=v(r)rc)e(r)=? dv(r)drd)e(r)=? v(r)r

Four friends, a, b, c, and d are standing varying distances away from a speaker which is producing sound waves.