A bobsled has a momentum of 4000 kg•m/s to the south. Friction on the track reduces its momentum to 2500 kg•m/s to the south. What impulse is
applied to the bobsled by the friction?

Which branches of natural science include the study of an organism that lived 10 million years ago

Aboy with a mass 25 kg climbs into a small tree. he sits on a branch that is 2.o m above to the ground.what is his gravitational potential energy above the ground?

Two 2.0-cm-diameter disks face each other, 1.0 mm apart. they are charged to ±10 nc. what is the electric field strength between the disks? a proton is shot from the negative disk toward the positive disk. what launch speed must the proton have to just barely reach the positive disk?