Two blocks are connected by a spring as shown in figure.The blocks are placed on a horizontal rough surface with `mu` as the coefficient of friction between the blocks and the surface.
Minimum horizontal force on `M_1` so as to move `M_2` is :
| A. |
`mu M_2g` |
| B. |
`mu (M_1-M_2)g` |
| C. |
`mu (M_1+M_2)g` |
| D. |
`mu/2 (2M_1+M_2)g` |
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