A heat engine takes heat QH from a hot reservoir and uses part of this energy to perform work W. Assuming that QH cannot be changed, how can the efficiency of the engine be improved? (a)Decrease the work W, the heat QC rejected to the cold reservoir remaining unchanged. (b)Increase the work W, the heat QC rejected to the cold reservoir increasing as a result. (c)Increase the work W, the heat QC rejected to the cold reservoir remaining unchanged. (d)Decrease the work W, the heat QC rejected to the cold reservoir decreasing as a result. (e)Increase the work W, the heat QC rejected to the cold reservoir decreasing as a result.

it has to be b, about 97 percent.

c. magnitude and direction

dec 23, 2016 - a load of bricks weighing 680 n a distance of 10 m across a parking lot. if if the worker pushes the cart with a constant force of 209 n, what work= force x distance = 220 n x 10 m = 2200 n.m = 2200 j i don't know where the person got it from, but the initial part, work= force x distance me.

igneous rocks also form where plates converge. the subducting plate melts as it sinks into the crust of the earth, and the melt rises into the overriding plate forming volcanoes. metamorphic rocks are formed mainly in the lithosphere, wherever there is high pressure and high temperature. -woods