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a 500 kg piano is being lowered into position by a crane while 2 people steady it with ropes pulling to the sides. bob's rope pulls to the left, 15 degrees below horizontal, with 500 N of tension. ellen's rope pulls toward the right, 25 degrees below horizontal. what tension must ellen maintain in her rope to keep the piano descending at a steady speed?
ok so what i understood from this, is that bobs rope is in the 3rd quad and ellens is in the 4th. and i guess there is a main cable from the crane going straight up. and then since is says it is descending at a steady speed that means that there is no net force or acceleration. so i figured i should get the components of bob's rope, Bx=-482 By=-129.
and the i thought that
Fnetx = Bx+Ex =0
-482 + Ecos25 =0
Ecos25=482
E=532
Fnety = By+Ey=o
-129+Esin25=0
E=306
and then i found the magnitude of the two components of E and 614 N. but that is incorrect. so i don't know what to do anymore!
ok so what i understood from this, is that bobs rope is in the 3rd quad and ellens is in the 4th. and i guess there is a main cable from the crane going straight up. and then since is says it is descending at a steady speed that means that there is no net force or acceleration. so i figured i should get the components of bob's rope, Bx=-482 By=-129.
and the i thought that
Fnetx = Bx+Ex =0
-482 + Ecos25 =0
Ecos25=482
E=532
Fnety = By+Ey=o
-129+Esin25=0
E=306
and then i found the magnitude of the two components of E and 614 N. but that is incorrect. so i don't know what to do anymore!