The direction of propagation of an e.m. wave is given by `vec Exx vec B`.(True/False)

The propagation vector of an electromagnetic wave is given by vec S = 2 hat i + 4 hat j + sqrt5 hat k Find the angle which the direction of propagation of the wave makes with X-axis.

If vec a , vec b are any two vectors, then give the geometrical interpretation of relation | vec a+ vec b|=| vec a- vec b|

Given three vectors vec a=6 hat i-3 hat j , vec b=2 hat i-6 hat ja n d vec c=-2 hat i+21 hat j such that vecalpha= vec a+ vec b+ vec cdot Then the resolution of the vector vecalpha into components with respect to vec aa n d vec b is given by a. 3 vec a-2 vec b b. 3 vec b-2 vec a c. 2 vec a-3 vec b d. vec a-2 vec b

Determine the lengths of the diagonals of a parallelogram whose adjacent sides are vec a=2 vec m+ vec n and vec b=vec m-2 vec n where vec m and vec n are unit vectors inclined at an angle of angle 60 .

The e.m. waves of radio frequency cannot be reflected by ionosphere. (True/False)

The e.m. waves of radio frequency cannot be reflected by ionosphere. (True/False)

Show that ( vec a- vec b)xx( vec a+ vec b)=2( vec axx vec b)dot

Show that perpendicular distance of the point vec c from the line joining vec a and vec b is (| vec bxx vec c+ vec cxx vec a+ vec axx vec b|)/(| vec b- vec a|)

Let ABCD be a parallelogram such that vec A B= vec q , vec A D= vec p""a n d""/_B A D be an acute angle. If vec r is the vector that coincides with the altitude directed from the vertex B to the side AD, then vec r is given by (1) vec r=3 vec q-(3( vec pdot vec q))/(( vec pdot vec p)) vec p (2) vec r=- vec q+(( vec pdot vec q)/( vec pdot vec p)) vec p (3) vec r= vec q+(( vec pdot vec q)/( vec pdot vec p)) vec p (4) vec r=-3 vec q+(3( vec pdot vec q))/(( vec pdot vec p)) vec p