(1 point) newton's law of cooling states that the temperature of an object changes at a rate proportional to the difference between its temperature and that of its surroundings. suppose that the temperature of a cup of coffee obeys newton's law of cooling. let k> 0k> 0 be the constant of proportionality. assume the coffee has a temperature of 190 degrees fahrenheit when freshly poured, and 33 minutes later has cooled to 180 degrees in a room at 68 degrees.(a) write an initial value problem for the temperature t of the coffee, in fahrenheit, at time t in minutes. your answer will contain the uknown constant k : dtdt=equation editort(0)=equation editor(b) solve the initial value problem in part (a). your answer will contain the unknown constant k .t(t)=equation editor(c) determine the value of the constant kk=equation editorminutes.(d) determine when the coffee reaches a temperature of 150 degrees. equation editorminutes.

Rank the torques on the five doors shown in the figure above from least to greatest. note that the magnitude of all the forces is the same

We want to calculate the total metabolic heat generated by a singing canary taking into account heat transfer by radiation, convection and exhaling air. the air temperature is 20 oc, canary’s body internal and surface temperature is 33oc, external body surface convective heat transfer coefficient is 25.2 w/m2 .k, temperature difference between the inhaled and exhaled air is 4.3 oc, the ventilation rate is 0.74 cc of air per second, specific heat of air is 1.0066 kj/kg.k and density of air is 1.16 kg/m3 . assume the canary’s body to be a cylinder with 7 cm diameter and 9 cm length, and heat exchange is from the side as well as the top and bottom of cylinder. calculate 1) the net rate of heat lost by radiation, assuming heat gained by the bird through radiation from the surroundings is 11.5 w; 2) rate of heat transferred by convection to the surrounding air; 3) rate of heat transferred in the exhaling air without considering any internal evaporation; 4) total metabolic power.

A30 kg weight lies on top of a massless piston of area a = 0.01 m2 the exterior air is at a (constant) p =1 atm and t = 27 c. the interior gas is 0.4 moles of (ideal) n2 and it has initial temperature 27.00 degrees c. 1. what is the initial pressure in the interior? a. 29.4 kpa b. 130.7 kpa c. 101.3 kpa the next three questions concern what happens when an amount of heat q is slowly added to the interior, raising the piston by 1 mm and raising the interior temperature to 27.40 c