Recent content by alessandro

Homework Statement a fire hose is turned on the door of a burning building in order to knock the door down. This requires a force a 1000 N. if the hose delivers 40 kg per second, what is the minimum velocity of the stream needed? assuming the water doesn't bounce back? Homework Equations...

i see..so now i get 80 and then i divded for 0,1 and i get 800 N

Homework Statement a 2 kg softball is pitched to u at 20 m/s. you hit the ball back along the same path, and at the same speed. IF the bat was in contact with the ball for 0.10 s, what is the magnitude of the average force the bat exerted? Homework Equations FAT=Pf-pi The Attempt...

because the gravitazional force points upward and the frictional force which is against the gravitazional force...it would be pointing downward

that frictional force point downward ?

the forces are the gravitazional force which points downward, friction force which acts in opposite direction of the car...

i don't really know..i'm lost..

the friction provides the force necessary right? But usually to find this force i need also the mass...

the agent provides the centripetal force...the agent proivdes also the acceleration right?

Friction provides the force needed for a car to travel around a flat, circular race track. What is the maximum speed at which a car can safely travel if the radius of the track is 80 m and the coefficient of friction is 0.40 ? I'm totally lost...hope u guys can help me