In both (a) and (b) the acceleration on the 5-kg box (M) is as large as it can be without the box sliding. Find the coefficient of static friction for each case if the magnitude of the acceleration is 4 m/s2.
(a) The box is on the bed of a truck that is accelerating on flat ground.
![683_The box is on the bed of a truck.png](https://secure.tutorsglobe.com/CMSImages/683_The%20box%20is%20on%20the%20bed%20of%20a%20truck.png)
(b) The box is in a skiing gondola on its way to the top of the mountain. The gondola does not swing during the motion.
![296_The box is in a skiing gondola.png](https://secure.tutorsglobe.com/CMSImages/296_The box is in a skiing gondola.png)