Chapter 9: Statics & Torque

These flashcards cover key concepts and definitions related to statics and torque from Chapter 9, which are essential for understanding the principles of mechanics as discussed in the lecture.

What is the study of forces in equilibrium called?

Statics.

What are the two conditions that must be satisfied for equilibrium?

The net external force must be zero in both x and y directions.

What is static equilibrium?

A state of rest or motionless.

What is dynamic equilibrium?

A state of constant velocity.

What is torque?

A measure of the effectiveness of a force in changing or accelerating a rotation.

How can torque be expressed?

Torque (τ) = r * F * sin(θ) where r is the distance, F is the force, and θ is the angle.

In what units is torque expressed?

Newton-meters (N m).

What makes a system in stable equilibrium?

When displaced from equilibrium, it experiences a restoring force or torque in the opposite direction.

What happens in unstable equilibrium?

When displaced, the system accelerates away from its equilibrium position.

What defines neutral equilibrium?

The equilibrium is independent of displacements from its original position.

What can be done to increase stability?

Lowering the center of gravity or increasing the base of support.

What is the purpose of a free body diagram?

To visualize the forces acting on a system and their relative magnitudes and directions.

What is the mechanical advantage?

The ratio of output to input force magnitudes for a simple machine.

What is an example of stable equilibrium?

A marble at the bottom of a bowl.

What happens when the center of gravity is no longer over the base of support?

It leads to instability.

What is the first step in solving static problems?

Determine whether or not a system is in static equilibrium.

What is indicated by the condition of zero net external torque on a system?

It must be in equilibrium regarding angular motion.

What does the term 'critical point' refer to in stability?

The point at which the system can no longer return to equilibrium after a displacement.