A 5.36×104 kgkg railroad car moves on frictionless horizontal rails until it hits a horizontal spring stopper with a force constant of 4.29×105 N/mN/m . When the railroad car comes to a complete stop, the compression of the spring stopper is 36 cmcm . How fast was the railroad car initially?

Patricia is trying to compare the average rainfall of new york to that of arizona. a comparison between these two states for the months of july through september would best be measured in

The receptor cells that convert light energy into neural signals are called

You are your friend move a new refrigerator into his kitchen. you apply a horizontal force of 252 n in the negative x direction to try and move the 56 kg refrigerator. the coefficient of static friction is 0.61. (a) how much static frictional force does the floor exert on the refrigerator? give both magnitude (in n) and direction. magnitude n direction (b) what maximum force (in n) do you need to apply before the refrigerator starts to move?