Ten questions. The result tells you which lessons you may skip.
A box rests on the flat floor of a truck that is speeding up while moving forward. The box does not slip. The friction on the box points
A \(5\,\text{kg}\) block on a \(37°\) incline, \(\mu_s = 0.25\), is tied over a pulley at the top to a hanging \(2.5\,\text{kg}\) mass. Take \(g = 10\,\text{m/s}^2\), \(\sin 37° = 0.6\), \(\cos 37° = 0.8\). What happens?
A block at rest on an incline is pulled up the slope. Assuming friction up the slope, the equations give \(f = -10\,\text{N}\), and the limit is \(40\,\text{N}\). The friction is
A \(10\,\text{kg}\) block rests on a \(37°\) incline with \(\mu_s = 0.5\). Take \(g = 10\,\text{m/s}^2\), \(\sin 37° = 0.6\), \(\cos 37° = 0.8\). The least pull up the slope that holds it is
A block rests by itself on an incline with \(\tan\theta < \mu_s\). Compared with the pull up the slope that just starts it moving up, the pull down the slope that just starts it moving down is
The coefficient of static friction between a block and a floor is \(\mu_s\). The angle of friction \(\lambda\) satisfies
A heavy box on a rough floor is pulled by a rope. The pull that starts the box is least when the rope makes, with the horizontal, an angle equal to
A \(2\,\text{kg}\) block lies on a \(4\,\text{kg}\) block on a smooth floor, with \(\mu_s = 0.3\) between them. Take \(g = 10\,\text{m/s}^2\). The largest force on the lower block for which they move together is
The same blocks, with \(\mu_k = 0.3\), are pulled by \(30\,\text{N}\) on the lower block, and the top block slips. The acceleration of the top block is
A box is placed at rest on a belt moving at \(2\,\text{m/s}\), with \(\mu_k = 0.2\). Take \(g = 10\,\text{m/s}^2\). How far does the box slide along the belt before it moves with the belt?