Friction

A wedge of inclination angle $\theta$ and mass $m$ is placed on a horizontal table. An object, also of mass $m$, is placed on the inclined surface of the wedge. The coefficient of friction between the object and the wedge, and between the wedge and the table, is $\mu$.

Block B, of weight $W_B$, rests on a horizontal table. The coefficient of static friction between the block and the table is $\mu_s$. A system of cords connects block B, a hanging block A of weight $W_A$, and a wall, with one cord making an angle $\theta$ with the horizontal. The system is in static equilibrium.

Three crates with masses $m_1$, $m_2$, and $m_3$ are being pushed over a floor by a horizontal force $\vec{F}$ applied to crate 1. The coefficient of kinetic friction between the floor and each crate is $\mu_k$.

A block of mass $m_A$ on an inclined plane at angle $\theta$ is connected by a rope over a frictionless, massless pulley to a hanging block of mass $m_B$. The coefficients of static and kinetic friction between block A and the incline are $\mu_s$ and $\mu_k$. The positive direction is defined as up the incline, represented by the unit vector $\hat{i}$.

Two blocks are connected over a frictionless, massless pulley as shown in the figure. The mass of block A is $m_A$. The coefficient of kinetic friction between block A and the incline is $\mu_k$. The angle of the incline is $\theta$. Block A slides down the incline at a constant speed. The connecting rope has negligible mass.

Two blocks A and B, with masses $m_A$ and $m_B$, are placed together on a horizontal table as shown in Figure (a). The contact surface between them is smooth and inclined at an angle $\theta$ to the horizontal. The coefficient of static and kinetic friction between each block and the table is $\mu$. A horizontal force F is applied to block A.

Block A of weight $W_A$ rests on a horizontal table. It is connected by a string passing over a frictionless, massless pulley to a hanging block B of weight $W_B$. A third block C, of weight $W_C$, is placed on top of block A. The coefficient of static friction between block A and the table is $\mu_s$, and the coefficient of kinetic friction is $\mu_k$.

Three blocks are stacked on a horizontal table. From top to bottom, their masses are $m_1 = 5m$, $m_2 = 3m$, and $m_3 = m$. A horizontal force $F$ is applied to the middle block, $m_2$. The coefficient of friction between block 1 and 2 is $4\mu$; between block 2 and 3 is $2\mu$; and between block 3 and the table is $\mu$. Assume the coefficients of static and kinetic friction are equal.

A boat of mass $m$ is traveling at an initial speed $v_i$ when its engine is shut off. The drag force from the water is proportional to the boat's speed $v$, given by $F_d = bv$, where $b$ is a constant drag coefficient.

A slab of mass $m_1$ rests on a frictionless floor. A block of mass $m_2$ rests on the slab. The coefficients of static and kinetic friction between the block and slab are $\mu_s$ and $\mu_k$, respectively. A horizontal force of magnitude $F$ is applied to the block in the positive x-direction.