1. An object is pushed with a force of 400 N for 20 meters; what is the work done on the object? Solve using W=F*d (page 107) 2. A truck has a mass of 3,000 kg and is going 3 m/s. What is the kinetic energy of the truck? Solve using KE = (1/2)mv2 (page 116)

3. A book has a mass of 6 kg and is 15 m above the ground; what is its potential energy? Solve using GPE = mgh (g = 9.81 m/s^2; page 118)

4. A power mower does 120,000 J of work in 1200 s. What power does it develop? Solve using P = E/t (page 126)​

Under conditions for which the same room temperature is maintained by a heating or cooling system, it is not uncommon for a person to feel chilled in the winter but comfortable in the summer. provide a plausible explanation for this situation (with supporting calculations) by considering a room whose air temperature is maintained at 20â°c throughout the year, while the walls of the room are nominally at 27â°c and 14â°c in the summer and winter, respectively. the exposed surface of a person in the room may be assumed to be at a temperature of 32â°c throughout the year and to have an emissivity of 0.90. the coefficient associated with heat transfer by natural convection between the person and the room air is approximately 2 w/m2 â‹…â‹… k. what is the ratio of the thermal resistance due to convection to the thermal resistance due to radiation in the summer? what is the ratio of thermal resistances in the winter

In the derivation of rrkm theory, a factor of 1/2 is introduced when equalizing the rates of formation and decomposition of activated complex as keal-hr) = ko this is clearly against the assumption of transition state theory that states all the activated complex in the transition state iss going to the product. find the reason why this factor is introduced here.

Dao makes a table to identify the variables used in the equations for centripetal acceleration. what quantities belong in cells x and y?