4. how much time would it take for an airplane to reach its destination if it traveled at an average speed of
780 kilometers/hour for a distance of 4,700 kilometers? what is the airplane's speed in miles/hour?
hint: show how you convert kilometers into miles for your calculation (1 mile = 1.6 km)
looking for which variable:
solution

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 ?

Four objects each with charge +2.0×10−7c are located at the corners of a square whose sides are 2.0 m long. part a what quantities can be determined using this information? check all that apply. the electric force on a charged object placed at the center of the square. the mass of each object. the total electric potential energy of the system consisting of the four charged objects. part b find the electric force on a charged object placed at the center of the square.

The record distance in the sport of throwing cowpats is 81.1 m. this record toss was set by steve urner of the united states in 1981. assuming the initial launch angle was 45° and neglecting air resistance, answer the following. (a) determine the initial speed of the projectile. m/s