One wall of a house consists of 0.019 m thick plywood backed by 0.076 m thick insulation. The temperature at the inside of the house is 25 degrees celsius, while the temperature on the outside of house is 4 degrees celsius, both being constant. The thermal conductivities of the insulation and plywood are 0.030 and 0.080, respectively and the are of the wall is 35m^2. a) Find the temperature at the plywood/insulation interface, assuming that no heat escapes from the system.
b) Find the quantity of heat conducted through the wall in one hour.

Awater balloon launcher uses an elastic band with a spring constant of 115 n/m to use thee launcher you stretch thee band back with a balloon n it the water balloons have a mass of 1.3 kg a) if you stretch the band by 0.8 m, what elastic force will the band exert? b) with the band stretched 0.8 m, how much elastic potential energy is stored in the spring? c) if you release the band, it pushes forward. what is the kinetic energy of the balloon when it reaches the natural length of the band? d) what is the speed of the balloon when it reaches the natural length of the band?

Sort the images based on whether there's a force of attraction or repulsion between the magnets shown. attraction repulsion

Review multiple-concept example 7 in this chapter as an aid in solving this problem. in a fast-pitch softball game the pitcher is impressive to watch, as she delivers a pitch by rapidly whirling her arm around so that the ball in her hand moves in a circle. in one instance, the radius of the circle is 0.626 m. at one point on this circle, the ball has an angular acceleration of 66.1 rad/s2 and an angular speed of 12.6 rad/s. (a) find the magnitude of the total acceleration (centripetal plus tangential) of the ball. (b) determine the angle of the total acceleration relative to the radial direction.