11. As stated earlier, the friction force acts in a direction opposite the motion of the block. 12. Figure a ) depicts the model, figure b ) the equation of motion with unknown friction force 13. The friction force is then caught by the stopper ( Black trapezoid ) mounted on the brake shield. 14. This leads to a great reduction in average friction force , explaining why such solids have a lubricant effect. 15. This provides a buoyancy force, " lifting " the glacier from the bed and reducing the friction force . 16. :: There is a fifth force on the container-the vertical friction force exerted by the wall. 17. These friction forces add up to a very large force ( all in accordance with the standard formula ). 18. These coefficients describe the two types of friction forces in terms of the reaction forces acting on the bodies. 19. If we suddenly cut the voltage, the friction force will still be there, slowing down the current. 20. At this point, the device relied upon the friction force between the cards to achieve some kind of randomness.
