The coefficient of static friction between Teflon and scrambled eggs is about ${}^{\mathbf{0}\mathbf{.}\mathbf{04}}$.What is the smallest angle from the horizontalthat will cause the eggs to slide across the bottom of a Teflon-coated skillet?

In Fig. 6-37, a slab of mass ${}^{{\mathbf{m}}_{\mathbf{1}}\mathbf{=}\mathbf{40}\mathbf{}\mathbf{k}\mathbf{g}}$ rests on a frictionless floor, and a block of mas ${}^{{\mathbf{m}}_{\mathbf{2}}\mathbf{=}\mathbf{10}\mathbf{}\mathbf{k}\mathbf{g}}$ rests on top of the slab. Between block and slab, the coefficient of static friction is ${}^{\mathbf{0}\mathbf{.}\mathbf{60}}$ , and the coefficient of kinetic friction is ${}^{\mathbf{0}\mathbf{.}\mathbf{40}}$ . A horizontal force of magnitude ${}^{\mathbf{100}\mathbf{N}}$ begins to pull directly on the block, as shown. In unit-vector notation, what are the resulting accelerations of (a) the block and (b) the slab?

In Fig. 6-24, a force acts on a block weighing ${}^{\mathbf{45}\mathbf{}\mathbf{N}}$.The block is initially at rest on a plane inclined at angle ${}^{\mathbf{\theta }\mathbf{=}{\mathbf{15}}^{\mathbf{0}}}$to the horizontal. The positive direction of the x axis is up the plane. Between block and plane, the coefficient of static friction is ${}^{{\mathbf{\mu }}_{\mathbf{s}}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{50}}$ and the coefficient of kinetic friction is ${}^{{\mathbf{\mu }}_{\mathbf{k}}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{34}}$. In unit-vector notation, what is the frictional force on the block from the plane when is (a) ${}^{\mathbf{(}\mathbf{-}\mathbf{5}\mathbf{.}\mathbf{0}\mathbf{}\mathbf{N}\mathbf{)}\hat{\mathbf{i}}}$, (b) ${}^{\mathbf{(}\mathbf{-}\mathbf{8}\mathbf{.}\mathbf{0}\mathbf{}\mathbf{N}\mathbf{)}\hat{\mathbf{i}}}$ , and (c) ${}^{\mathbf{(}\mathbf{-}\mathbf{15}\mathbf{}\mathbf{N}\mathbf{)}}$?

A 100 N force, directed at an angle $\mathit{\theta }$ above a horizontal floor, is applied to a 25.0 kg chair sitting on the floor. If $\mathit{\theta }\mathbf{=}\mathbf{0}\mathbf{°}$, what are (a) the horizontal component ${\mathit{F}}_{\mathbf{h}}$ of the applied force and (b) the magnitudeN of the normal force of the floor on the chair? If $\mathit{\theta }\mathbf{=}\mathbf{30}\mathbf{.}\mathbf{0}\mathbf{°}$, what are (c) ${\mathit{F}}_{\mathbf{h}}$ and (d) ${\mathit{F}}_{\mathbf{N}}$? If $\mathit{\theta }\mathbf{=}\mathbf{60}\mathbf{.}\mathbf{0}\mathbf{°}$, what are (e) ${\mathit{F}}_{\mathbf{h}}$ and (f) ${\mathit{F}}_{\mathbf{N}}$? Now assume that the coefficient of static friction between chair and floor is 0.420 . Does the chair slide or remain at rest if $\mathit{\theta }$ is (g) $\mathbf{0}\mathbf{°}$, (h) $\mathbf{30}\mathbf{.}\mathbf{0}\mathbf{°}$, and (i) $\mathbf{60}\mathbf{.}\mathbf{0}\mathbf{°}$?

In Fig. 6-39, a car is driven at constant speed over a circular hill and then into a circular valley with the same radius. At the top of the hill, the normal force on the driver from the car seat is 0. The driver’s mass is ${}^{\mathbf{70}\mathbf{.}\mathbf{0}\mathbf{}\mathbf{kg}}$.What is the magnitude of the normal force on the driver from the seat when the car passes through the bottom of the valley?

Calculate the magnitude of the drag force on a missile 53 cm in diameter cruising at 250 m/s at low altitude, where the density of air is $\mathbf{1}\mathbf{.}\mathbf{2}\mathbf{}\mathbf{kg}\mathbf{/}{\mathbf{m}}^{\mathbf{3}}$. Assume $\mathbf{C}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{75}$.