# DDP Chapter 6

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# Links for the Sixth Chapter

This video shows you how balloons can be used as accelerometers. The hanging one acts like the ball in Experiment 6.1, while the floating one acts in an opposite fashion because it is floating in the air.

This video shows you how an accelerometer in a cell phone works.

This video shows you how to solve a static translational equilibrium problem.

This video shows you why the component of gravity parallel to the incline is mgsin(theta) and the component perpendicular is mgcos(theta).

This video shows you how to solve an incline problem without friction, then with friction.

This video shows you how to solve another kind of incline problem.

This video shows you how to solve a problem with two objects connected by a string, rope, or chain.

This video gives a demonstration of how torque changes with lever arm.

This video gives a practical application of lever arm and torque.

This video shows you what happens when the torques don’t balance. The candle melts more quickly on the side that is tilted down, which lowers the weight and therefore the torque that is causing the tilt. Eventually, that torque decreases so much that the other torque is stronger, causing the candle to tilt in the other direction.

This video shows you how to solve a problem with torques.

Extra Practice Problems
Here are the extra practice problems for Chapter 6. The solutions are here.