An object has a velocity of 8 m/s and a kinetic energy of 480 j. what is the mass of the object?

When you push downward on a book at rest on a table, you feel an upward force. does this force depend on friction? defend your answer.

Acarpenter builds an exterior house wall with a layer of wood 2.9 cm thick on the outside and a layer of styrofoam insulation 2.3 cm thick on the inside wall surface. the wood has k=0.080w/(m⋅k), and the styrofoam has k= 0.010 w/(m⋅k). the interior surface temperature is 19.0 ∘c , and the exterior surface temperature is -15.0 ∘c . a.)what is the temperature at the plane where the wood meets the styrofoam? celsius b.)what is the rate of heat flow per square meter through this wall? /m^2

What is the single most important equation in all of physics?