In the figure below, the pulleys and the cord are light, all surfaces are fricti
ID: 1779119 • Letter: I
Question
In the figure below, the pulleys and the cord are light, all surfaces are frictionless, and the cord does not stretch. (a) How does the acceleration or block 1 compare with the acceleration or block 2? Use the Ollo ing as necessary, ma m2 and 2 9.8-a2 2m1 Pl2 al = Explain your reasoning This answer has nat been graded yet (b) The mass of block 2 is 1.39 kg. Find its acceleration as it depends on the mass mi of block 1. (Use the following variable as necessary: m) magnitude direction (c) What does the result of part (b) predict if mi is very much less than 1.39 kg? (d) What does the result of part (b) predict if mi approaches infinity? .>M m/s (e) In this last case, what is the tension in the cord? E11 n culd you anticipate the answers (c). (d), and (e) without first doing part(b), Yes O No Explain your answer.Explanation / Answer
a) a x 2T = T x 2a
=> a1 = 2a2 ( from diagram it is very clear that for the travel of distance d of mass m2, m1 will travel 2d)
b) m2g - 2T = m2a
T = m1(2a)
=> m2g - 4m1a = m2a
=> a2 = a = m2g/(4m1 + m2) (downwards)
c) a2 = g = 9.8 m/s
d) a2 = 0
e) tension in cord = m2g/2 = 1.39 x 9.8/2 = 6.811 N
f) yes
as if m1 = 0, m2 will move due to only its own weight = free fall
if m1 is too high, m2 can't move (though it will have a little acceleration but it will be negligibly very very small)
again Tension comes from weight only as no acceleration is involved.