22.The two masses shown in the figure are attached by a massless string through
ID: 1656283 • Letter: 2
Question
22.The two masses shown in the figure are attached by a massless string through a pulley. The mass of m is 10.5 kg. The mass of m2 is 4.3 kg. m1 f.The system is at rest, on the verge of slipping. What is the coefficient of static friction betweern the table and mass 1? g.What is the tension in the string while the system is at rest? m2 h.A slight push to the right is given to mass 1 and the system begins to move with an acceleration of 0.30 m/s2. What is the coefficient of kinetic friction? i. What is the tension in the string while the system is in motion?Explanation / Answer
22:
(f) on m2: T - m2 g = 0
T = m2 g
on m1: T - f = 0
m2 g = us m1 g
us = m2 / m1 = 4.3 / 10.5
us = 0.41 ........Ans
(g) T = m2 g = 4.3 x 9.8
T = 42.14 N ........Ans
(h) on m2: 4.3g - T = 4.3 a
T = 4.3 (9.8 - 0.30) = 40.85 N
now on m1: T - fk = m1 a
T - uk m1 g = m1 a
40.85 - (10.5 x 0.30) = uk x 10.5 x 9.8
uk = 0.37
(i) T = 40.85 N