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reddeffect
Nov18-09, 10:51 PM
an elevator weighing 2x10^5n supported by a cable what is the tension on the cable when accelerating up is 3m/s2 g=9.8 obviously

and

an ice skater moves at 10 m/s and coasts to a halt in 100 meters on smooth ice what is the coefficient of friction on skates/ice

i have tried many different ways and am not coming up with the answer i was given any help is greatly appreciated.

Jack21222
Nov18-09, 10:59 PM
It might be worthwhile to post some of the "many different ways" you've attempted, as per the template which you deleted when you posted.

donhubix
Nov19-09, 03:29 AM
Question A-elevator)

Forces pointing downwards: Weight of lift
Forces pointing upwards: Tension force, ma(where m and a are mass and acceleration of lift respectivelly)

Balance the two equations to find the missing link: The tension force.

QuestionB-ice skater)

Do exactly the same:

From the data given (v and s) you can find the acceletarion(or rather deceleration), from this the coefficient of friction can be found easily.