A 90kg bicycle and rider are traveling at 3m/s then start coasting down a hill. While coasting, the rider sees a branch lying across the trail right where the trail flattens out and skids to a stop. (Assume no friction until the rider starts breaking.) Required:
a. If the rider coasted 30m, and descended 9m in the process, what is his speed when he starts breaking?
b. How much heat does the braking generate?
c. If the specific heat of the tire's rubber is 2000J/kg K, 50g of tire are in thermal contact with the ground and 40% of the heat generated goes into the tire, how much does the tire heat up?
d. If it is not an emergency, why might pulsing your braking (compressing and releasing the brake several times while stopping) help prolong the life of your brakes?

this allows people to make the best decision or pursue the best option. when alternatives are weighed using their advantages and disadvantages, the option whose disadvantages outweigh the advantages (based on a qualitative or quantitative analysis) are shunned while those whose advantages outweigh their disadvantages are pursued.  

force tends to be low and long diustance masses are high

as we probably am aware that our atmosphere or air have various levels, each level has different gasses, and each gas has another porousness. at the point when the light originates from lower porousness to higher penetrability, it alters its course. with the goal that implies that when the light originates from the moon to the earth, it alters it's course a lot more occasions. it essentially implies that the state of the light piece of the moon is changed on the earth.

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joke:

h o h o hope you have a merry christmas!

this is an example of "committed" time.

committed time, as contracted time, takes need over essential and available time since it is seen as profitable work. it alludes to the time allotted to keep up a home and family. at the point when a man is commuting using committed time this individual may feel that the drive is an obligation to family, for example, strolling youngsters to class or driving a mate to work. contracted and committed time clients may feel that their commute could really compare to the commute of important or leisure time clients on the grounds that their commute is profitable work. in this manner, they might be more disposed to pick a mechanized method of movement.