An object is whirled around in a horizontal circle fast enough that the string is practically horizontal, too. If the object is whirled in the same size circle but twice as fast, the tension in the string will be: a. twice as much as when going half the speed.
b. four times as much as when going half the speed.
c. the same as when going half the speed.
d. half as much as when going half the speed.
e. one fourth as much as when going half the speed.

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