Friction always acts in the same direction as motion.
in the opposite direction as motion.
at a 30 degree angle to the direction of motion.
perpendicular to the direction of motion.

What object a collides with object b and bounces back its final momentum is?

There are two-speed cameras, one in an are where the speed limit is 30 km/h and another where the speed limit is 50 km/h. in which will there be a smaller time interval between the photographs? explain your answer.

The star betelgeuse is about 600 light-years away. if it explodes tonight, a. we'll know because debris from the explosion will rain down on us from space.b. we'll know it immediately because it will be brighter than the full moon in the sky.c. we won't know about it until 600 years from now.d. none of the above.