Question

current attempt in progress
the drawings show identical blocks at rest on three different inclines, each block held in place by static friction. rank the forces of static friction in the three cases in ascending order (smallest first).
o b, a, c
o b, c, a
o a, c, b
o a, b, c
o c, a, b

Explanation:

Step1: Analyze force equilibrium

For a block of mass $m$ on an incline of angle $\theta$ held at rest by static - friction $f$, the force of static friction balances the component of the gravitational force along the incline. The component of the gravitational force along the incline is $F = mg\sin\theta$, where $g$ is the acceleration due to gravity.

Step2: Compare angles

The steeper the incline, the larger the value of $\sin\theta$. Let $\theta_A$, $\theta_B$, and $\theta_C$ be the angles of inclines A, B, and C respectively. From the figure, we can see that $\theta_B<\theta_C<\theta_A$.

Step3: Determine friction force ranking

Since $f = mg\sin\theta$ and $m$ and $g$ are constant, the force of static friction is proportional to $\sin\theta$. So, $f_B

Answer:

B, C, A