An elevator weighing 20,000 N is supposed by a steel cable. What is the tension in the cable when the elevator is being accelrated upward at a rate of 3.0 m/s^2.
Would it be: (20,000)(3.0) + (20,000)(9.8) = 26,100N?
please help, I'm confused with this one, thanks!
2007-02-14 02:07:21 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Physics
see there is a force of 20,000 N acting downwards.also a force of (20,000/9.8)*3 acting downwards. so tension is 20,000+ 6122.448 = 26122.448 N.
maybe u got confused by the pseudo force of acc = 3 m/s^2
2007-02-14 02:40:38 · answer #1 · answered by ashwin parihar 2 · 0⤊ 0⤋
just do F=ma
find all the forces acting on the elevator and equate it to the mass times acceleration
Draw a free body diagram of the elevator
there are only forces and acceleration in the y direction
the forces in the y direction are the tension and its weight
the acceleration is in the upwards y direction so solve for tension
T+W=M(a)
T-20,000=(20,000/9.81) * 3
T=26,116 newtons
By the way Juni's answer is calling 20,000 newtons the mass of the elevator if you look she multiplies this by the acceleration, this is wrong, the mass is its weight divided by the acceleration of gravity, or 20,000/9.81. Don't follow her answer or you will be wrong.
2007-02-14 02:14:48 · answer #2 · answered by poseidenneptune 5 · 0⤊ 0⤋
20,000 / 9.8 = 2040.816 kg
2040.816 X (9.8 + 3) = 26122.449 N
2007-02-14 02:23:15 · answer #3 · answered by Anonymous · 0⤊ 0⤋
T=w+ma
m is the mass so
m=20000/9.8=2040.8
T=20000 +(2040.8*3)=26122.54 N
be carful for the dirction if its down ward it will be -ma
good luck
2007-02-14 02:17:51 · answer #4 · answered by koki83 4 · 0⤊ 0⤋