A driveway (density 2115 kg/m3 , conductivity 0.062 W/m K, specific heat 920J/kg K) initially at a uniform temperature of 55C, was hosed to suddenly bring its surface to 25C, and maintain at that temperature. a. Give a rough sketch of how the temperature will vary with depth at 3 different time instants after the hose was turned on indicating the surface temperature and the temperature far below the surface in the sketch. b. Estimate the temperature at a depth 3 cm below the surface after an hour, clearly stating the assumptions that underlie your solution. c. At that time instant (after an hour) what will be the heat flux at the surface and in which direction

Describe how the fermi level changes with donor level, temperature and contact with p and n type semiconductors

I'm kinda lost ! 1. when marilyn takes her pet dog for a walk, the dog walks at a veryconsistent pace of 0.55 m/s. draw a position-time graph to representmarilyn's dog walking the 19.8 m distance from the front of her house tothe nearest fire hydrant.2. both car a and car bleave school when a stopwatch reads zero. car atravels at a constant 75 km/h, and car b travels at a constant 85 km/h.a) draw a position-time graph showing the motion of both cars. howfar are the two cars from school when the stopwatch reads 2 hrs? calculate the distances and show them on your graph.b) both cars passed a gas station 120 km from the school. when dideach car pass the gas station? calculate the times and show themon your graph.3. the figure below shows the position-time graph showing a shopper'smovement up and down the aisle at a store.a) write a story describing the shopper's movements at the store.b) when does the shopper have a position of 6 m? c) how much time passes between when the shopper enters the aisleand when he gets to a position of 12 m? what is the shopper's averagevelocity between 37 s and 46 s?

The charge on a charged sphere is: a)concentrated at its centerb)distributed uniformly throughout its volumec)clustered on its centerd)distributed uniformly over its surface