Arocket sled used in old air force test could accelerate a volunteer at rates of 90m/s^2. with this acceleration being constant, how long would it take for one of these rocket sleds to travel the length of a one kilometer test track if it starts from rest? a) 11.1sec b) 22.2sec c)4.71sec d) 32.2sec

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 ?

This punnett square shows the cross between two pants. one parent has round seeds (rr). and the other parent has wrinkled seeds (rr) which best describes their offspring as shown in this cross?

What would be the strength of earth's gravitational field at a point where an 80.0 kg astronaut would experience a 80% reduction in weight