Chapter 16, problem 63. a person is standing in a room at 18 ◦c. the exposed surface area and skin temperature of the person are 1.7 m2 and 32 ◦c, respectively, the convection heat transfer coefficient is 5 w/m2 ·k, and the emissivity of the skin and clothes is 0.9. determine the total rate of heat transfer.

If the force applied to an object remains constant, is more power needed for the object to move faster ? explain

As part of your daily workout, you lie on your back and push with your feet against a platform attached to two stiff springs arranged side by side so that they are parallel to each other. when you push the platform, you compress the springs. you do an amount of work of 79.0 j when you compress the springs a distance of 0.230 m from their uncompressed length. (a) what magnitude of force must you apply to hold the platform in this position? (b)how much additional work must you do to move the platform a distance 0.230 m farther? (c) what maximum force must you apply to move the platform a distance 0.230 m farther?

Smallest intensity of a stimulus that you can detect 50 percent of the time is