How Does a Cookie Jar's Motion on an Incline Relate to Physics Principles?

[lethalblade]

1.) A cookie jar is moving up a 39.7o incline. At a point 0.56 m from the bottom of the incline (measured along the incline), it has a speed of 1.48 m/s. The coefficient of kinetic friction between the jar and incline is 0.15.

(a) How much farther up the incline will the jar move?

(b) How fast will it be going when it slides back to the bottom of the incline?

2.) A pendulum (87cm long) with a 0.75kg bob is released from rest at an initial angle of theta with the vertical. At the bottom of the swing, the speed of the bob is 2.9m/s. Find the initial angle theta:

A pendulum (87cm long) with a 0.75kg bob is released from rest at an initial angle of theta with the vertical. At the bottom of the swing, the speed of the bob is 2.9m/s. What angle does the pendulum make with the vertical when the speed of the bob is 1.1 m/s?

Any help would be greatly appreciated.

 

[hotvette]

Please let us know what approach you are supposed to be using (e.g. F=ma, work-energy, etc.) and describe what you've tried so far and where you are stuck.

https://www.physicsforums.com/showthread.php?t=94379