In the given figure the blocks A, B and C weigh 4 ~kg, 6 ~kg and 8 kg respectively. The co-efficient of sliding friction between any two surfaces is 0.5. The force F required to slide the block C with constant speed is

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Correct answer: D. Statement I is false but Statement II is true

For the 8 kg block (C) to move with constant velocity,

F_{net} = 0

.

Friction forces acting:
- Between C and ground:

f = \mu(m_A + m_B + m_C)g = 0.5 \times (4+6+8) \times 10 = 90

N
- Between C and B:

f = \mu(m_A + m_B)g = 0.5 \times (4+6) \times 10 = 50

N

For the 6 kg block (B):

T = f_{\text{B on ground}} + f_{\text{A on B}}

T = \mu(m_A + m_B)g \cdot \frac{m_B}{m_A+m_B} + \mu \cdot m_A \cdot g

T = 20 + 50 = 70

N

For the 8 kg block (C):

F = 90 + T + 50 = 90 + 70 + 50 = 210

N

In the given figure the blocks A, B and C weigh 4 ~kg, 6 ~kg and 8...

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