contestada

1. The sketch shows two 4 kg blocks on a horizontal surface, joined by a string S. They are attached to a 2 kg mass by another string which passes over a frictionless pulley, allowing the 2 kg mass to hang freely. Each of the blocks experiences 6 N of friction.
a) Show that the system accelerates to the right at 0.8 m/s². Calculate the tension in string S.
b) 4 kg S 4 kg 2 kg [4] [4]
​

Respuesta :

Answer:

M g - T =  M a     acceleration of hanging block   (M = 2)

2 g - T = 2 a        where M = 2

T = 2 g - 2 a

T = 8 * a + 12 N       acceleration of blocks on table

2 g - 2 a = 8 a + 12

10 a = 2 g - 12  

a = .8 m/s^2   (assuming g = 10 m/s^2)

T = 2 g - 2 a = 2 * 10 - 2 * .8 = 20 - 1.6 = 18.4 N

Check: For blocks on table

a = (18.4 - 12) / 8 = 6.4 / 8 = .8 m/s^2

Otras preguntas