Depending on the roads taken:
It takes about 19 hours drive 1142 miles.
A long time
If you are asking about the Cornwall in England, then you can't drive from there to Los Angeles, because of the ocean.
A drive from Las Vegas to Los Angeles would take about 70 hours.
few days
50 hours
One side of North America to the other is about 73 hours.
30 to 45 minutes, give or take, and provided traffic isn't too bad.
37 hours
about 45 mins
an hour and a half