A jeep drives a distance d = 27 m in the positive x-direction in a time of t1 = 22.5 s. The jeep immediately brakes and comes to rest in t2 = 9 s.
Randomized Variables
d = 24.5 m
t1 = 19.5 s
t2 = 6 s
a. What was the jeep's average velocity in the horizontal direction, in meters per second, during t1?
b. What was the acceleration, in meters per second, squared, during time interval t1, assuming the jeep started from rest and moved with constant acceleration?
c. What was the jeep's instantaneous velocity in the horizontal direction, in meters per second, when it began braking?
d. Using the result from part (c), what was the jeep's horizontal component of acceleration, in meters per second squared, during the braking period?

When you drop a pebble from height a it reaches the ground with speed v if there is no air resistance. from what height should you drop it so it will reach the ground with three times the speed? (a) 9m (b) 3m (c) 6m (d) 18m

Occurs when an energy source transfers heat directly to another subject space; an example would be an object becoming warm by sitting in the sunshine

An internally reversible refrigerator has a modified coefficient of performance accounting for realistic heat transfer processes of where qin is the refrigerator cooling rate, qout is the heat rejection rate, and is the power input. show that copm can be expressed in terms of the reservoir temperatures tc and th, the cold and hot thermal resistances rt,c and rt,h, and qin, as where rtot rt,c rt,h. also, show that the power input may be expressed as 1.39 a household refrigerator operates with cold- and hot-temperature reservoirs of tc 5 c and th 25 c, respectively. when new, the cold and hot side resistances are rc,n 0.05 k/w and rh,n 0.04 k/w, respectively. over time, dust accumulates on the refrigerator’s condenser coil, which is located behind the refrigerator, increasing the hot side resistance to rh,d 0.1 k/w. it is desired to have a refrigerator cooling rate of qin 750 w. using the results of problem 1.38, determine the modified coefficient of performance and the required power input w under (a) clean and (b) dusty coil conditions. internally reversible refrigerator qout qin w high-temperature reservoir low-temperature reservoir th th,i tc,i tc high-temperature side resistance low-temperature side resistance w qin th tc qinrtot tc qinrtot copm tc qinrtot th tc