(Solved): 14. A driver in a 1000kg car traveling at 20m/s slams on the brakes and skids to a stop. If the ...

14. A driver in a $1000\mathrm{kg}$ car traveling at $20\mathrm{m}/\mathrm{s}$ slams on the brakes and skids to a stop. If the coefficient of friction between the tires and the horizontal road is 0.80 , how long will the skid marks be? 15. A factory robot drops a $10\mathrm{kg}$ computer onto a conveyor belt running at $3.1\mathrm{m}/\mathrm{s}$. The materials are such that ${?}_{\mathrm{S}}=0.50$ and ${?}_{\mathrm{k}}=0.30$ between the belt and the computer. How far is the computer dragged before it is riding smoothly on the belt? 16. In the figure, a block of mass $M$ hangs at rest. The rope that is fastened to the wall is horizontal and has a tension off $52\mathrm{N}$. The rope that is fastened to the ceiling has a tension of $91\mathrm{N}$, and makes an angle $?$ with the ceiling. What is the angle $?$ ? 17.The magnitude of the drag force of air resistance on a certain $20.0?\mathrm{kg}$ object is proportional to its speed. If the object has a terminal speed $80.0\mathrm{m}/\mathrm{s}$, what is the magnitude of the drag force on the object when it is falling with a speed of $30.0\mathrm{m}/\mathrm{s}$ ? 18. A $1.20?\mathrm{kg}$ ball is hanging from the end of a rope. The rope hangs at an angle of $25.0^{?}$ from the vertical when a $15.0\mathrm{m}/\mathrm{s}$ horizontal wind is blowing. If the wind's force on the rope is negligible, what drag force does the wind exert on the ball? 19. An $80.0?\mathrm{kg}$ object is falling and experiences a drag force due to air resistance. The magnitude of this drag force depends on its speed, $v$, and obeys the equation $F_{\text{drag }}=(12.0\mathrm{N}?\mathrm{s}/\mathrm{m})v+\left(4.00\mathrm{N}?{\mathrm{s}}^2/{\mathrm{m}}^2\right)v^2$. What is the terminal speed of this object?