What is the electric potential v created at distance z above the center of a 20 lepta 1971 greek coin that has been charged with total charge q? treat the coin as a disk with a hole, so that its inner radius is a and its outer radius is b.

Space-time metric ds2= -dt2+at2dx2+bt2dy2+ct2dz2 (a)how does the area of a rectangle with vertices at ( x=0, y=0, z=0 ), (1,0,0 ), ( 0,1,0 ) and (1,1,0 ) changes with time? (b) if a photon moving in the x direction starts from the origin at t=1, when does it reach x=l? (ds=0 for the trajectory of a photon.) (c) the proper time for a particle is defined by cd=ds. what is the proper time for a particle to move along the trajectory ( x(t)=t, y(t)=0, z(t)=0 ) from t=0 to 1 ? what is the condition on the parameter a so that the velocity of the particle never exceeds the speed of light ?

What is work? how much work is done to move an object 0 meters?

The government has declared that a hurricane is likely to hit the east coast. which government division is part of acf and provides guidance to citizens? a. job opportunities for low-income individuals b. office of human services emergency preparedness and response c. assets for independence d. low-income home energy assistance program