To determine the magnitude of the acceleration of the block across the floor, we need to analyze the forces acting on it and check if the block overcomes static friction. If it does, we then calculate its acceleration under kinetic friction.

Given Data:

• Block mass = $m$
• Force applied $F = 0.500mg$
• Angle $\theta = 20.0^{\circ}$
• Gravitational force $mg$
• (a) Static friction coefficient $\mu_s = 0.610$ and kinetic friction coefficient $\mu_k = 0.510$
• (b) Static friction coefficient $\mu_s = 0.410$ and kinetic friction coefficient $\mu_k = 0.340$

Step-by-Step Process:

1. Components of the applied force:

   • Horizontal component: $F_x = F \cos \theta = 0.500mg \cos \theta$
   • Vertical component: $F_y = F \sin \theta = 0.500mg \sin \theta$

2. Normal Force: The normal force $N$ is affected by the vertical component of the applied force: $N = mg - F_y = mg - 0.500mg \sin \theta$ Simplifying: $N = mg(1 - 0.500 \sin \theta)$

3. Static Friction: The maximum static friction force $f_s$ is: $f_s = \mu_s N = \mu_s mg(1 - 0.500 \sin \theta)$

4. Check if the block moves: The block will move if the horizontal component of the applied force $F_x$ exceeds the maximum static friction force $f_s$. Compare $F_x$ with $f_s$: $F_x = 0.500mg \cos \theta$ So, if $F_x > f_s$, the block moves. Otherwise, it remains stationary.

5. If the block moves, calculate acceleration: If the block moves, use the kinetic friction force $f_k$ to find the net force and thus the acceleration: $f_k = \mu_k N = \mu_k mg(1 - 0.500 \sin \theta)$ The net horizontal force is: $F_{\text{net}} = F_x - f_k$ Using Newton's second law, the acceleration $a$ is: $a = \frac{F_{\text{net}}}{m} = \frac{F_x - f_k}{m}$

(a) For $\mu_s = 0.610$ and $\mu_k = 0.510$:

Let's calculate:

• $F_x = 0.500mg \cos 20^\circ$
• $F_y = 0.500mg \sin 20^\circ$
• $N = mg(1 - 0.500 \sin 20^\circ)$
• $f_s = \mu_s N$
• $f_k = \mu_k N$

(b) For $\mu_s = 0.410$ and $\mu_k = 0.340$:

Repeat the same steps as in part (a) but with the new friction coefficients.

Let's compute the exact results.### Results:

• (a) For $\mu_s = 0.610$ and $\mu_k = 0.510$: The block does not move, so the acceleration is $0$.
• (b) For $\mu_s = 0.410$ and $\mu_k = 0.340$: The block moves, and the acceleration is approximately $0.188 \, \text{m/s}^2$.

Would you like further details on any of the calculations, or have any questions?

Here are 5 follow-up questions:

1. How do different angles of applied force affect the motion?
2. What happens if the applied force is increased?
3. How would increasing the mass change the results?
4. Can we calculate the work done by the applied force?
5. How does the difference between static and kinetic friction impact acceleration?

Tip: To maximize the block's motion, minimize the angle or apply the force horizontally!