A football player runs down the field with a speed of 8 m/s. How long will it take him to run 20 m?
A. 160 s
B. 5.5 s
C. 2.5 s.
D. 0.4 s

For the car in the picture ,in which direction is the normal force? -into the screen -down -out of the screen -up

Asolid cylinder and a cylindrical shell have the same mass, same radius, and turn on frictionless, horizontal axles. the cylindrical shell has light-weight spokes connecting the shell to the axle. a rope is wrapped around each cylinder and tied to blocks of equal masses that are held the same height above the ground. both blocks are released simultaneously. the ropes do not slip. which block hits the ground first? or is it a tie?

"if the pressure acting on an ideal gas at constant temperature is tripled, its volume isa) reduced to one-third.b) increased by a factor of three.c) increased by a factor of two.d) reduced to one-half"