Part 1: In the Figure, a block m1 sits on a table. There is static friction betw
ID: 1335999 • Letter: P
Question
Part 1: In the Figure, a block m1 sits on a table. There is static friction between block and table. Block m2 hangs from a knot, as shown. Call the tension in the rope connecting the knot to m1, "T1". Call the tension in the rope connecting the knot to m2, "T2". Call the tension in the third rope (the one tipped up by an angle theta, connecting the knot to the wall), "T3". The system is in equilibrium. Which of the following statements are true? (If A and E are true, and the others are not, enter TFFFT)
A) The tension T2 must equal m2 g
B) If the table was completely frictionless, the system as shown could not be in equilibrum
C) The net force on the knot is zero.
D) The force of static friction on m1 equals T1
E) T3 is equal in magnitude to T1
Part 2: In the previous problem, block m1 weighs 760 N. The coefficient of static friction between the block and the table is 0.27 and the angle theta is 27.5o. Find the maximum weight of block m2 for which block m1 will remain at rest.
Explanation / Answer
along vertical
T2 = m2*g
T3*sintheta = T2 = m2*g
T3 = m2g/sintheta
along horizantal
T1 = T3*costheta
T1 = m2g/tantheta
for m1
T1 = f
m2*g/tantheta = us*m1*g
A)
TRUE
B)
TRUE
C)
TRUE
D)
FALSE
E)
FALSE
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part(2)
from the equation
m2*g/tantheta = us*m1*g
m2*9.8/tan27.5 = 0.27*760
m2 = 10.9 kg <<<----answer