MCQ
A block weighs $W$ is held against a vertical wall by applying a horizontal force $F$. The minimum value of $F$ needed to hold the block is $[\mu < 1]$
- ALess than $W$
- BEqual to $W$
- ✓Greater than $W$
- DData is insufficient
✓
Answer
Correct option: C.
Greater than $W$
c
The figure show the free body diagram of block.
The figure show the free body diagram of block.
Here, the force of friction is equal to the weight of block.
$f=W$
$\mu R = W$
$\therefore F =\frac{ W }{\mu}$
As,
$\mu < 1$
$\therefore F > W$
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