Two masses A and B of 15 kg and 10 kg are connected with a string passing over a frictionless pulley fixed at the corner of a table (as shown in figure). The coefficient of friction between the table and block is 0.4. The minimum mass of C, that may be placed on A to prevent it from moving is:

Options

A. 10 kg
B. 5 kg
C. zero
D. 15 kg

Answer

A

Explanation

`m_(B) g = (m_(A) + m_(C )) mu g` , `10 = (15 + m_(c )) xx 0.4` `:. M_(c ) = 10 kg`