A)The magnetic field component of the electromagnetic wave is 15.0 ?T. What is t
ID: 1376704 • Letter: A
Question
A)The magnetic field component of the electromagnetic wave is 15.0 ?T. What is the energy density of the wave?
B)An object is placed between C and F in front of a concave mirror with a focal length of 10 cm. What is the position of its image in relation to the mirror and what are its characteristics?
C)Light of wavelength ? = 540 nm passes through a pair of slits with separation 3.4 10-5 m. What is the angle corresponding to the second bright fringe?
D)Astronaut Sarah leaves Earth in a spaceship at a speed of 0.28 c relative to Earth. Sarah's destination is a star system 12.5 light-years away. According to Sarah, how far did she travel during the trip?
E)At what speed is the mass of an electron double its rest mass (m = 2 m0)?
Explanation / Answer
Please note that we are not allowed to answer more than one question at a time therefore I am answering the very first one.
(1) Energy density of the electromagnetic wave in the magnetic field is U = (1/2u)B2
where u is the magnetic permeability and the B is the magnetic field component
therefore U = (1/2u)(15)2 = 112.5/u TA/m
on putting the value of u = 4(Pi)*10-7 Tm/A
U = 8.952*107 TA/m
I am also giving little extension on second one.
The image will be magnified and inverted and we can find the value of the distance of image on putting the value of the distance of the object (u)
Mirror formula (1/f) = (1/u)+(1/v) where f is focal length , v is the distance of the image formed.