Mechanical Phenomena

Understanding everyday mechanical phenomena and why objects behave as they do

Topics

How does a lever work?

A lever works by using a rigid bar that pivots on a fulcrum. Applying force at one point creates a larger force at another point, allowing you to lift heavy objects with less effort. The mechanical advantage depends on the distances from the fulcrum to the force and load.

How does a pendulum work?

A pendulum works by converting between potential and kinetic energy as it swings. Gravity pulls the pendulum downward, and inertia carries it past the bottom, creating oscillating motion. The period (swing time) depends on length and gravity, not mass or amplitude.

Why do objects fall at the same rate?

Objects fall at the same rate (in vacuum) because gravity accelerates all objects equally, regardless of mass. Heavier objects have more gravitational force, but they also have more mass, so the acceleration (force divided by mass) is the same for all objects.

Why do we feel weightless in space?

We feel weightless in space because we're in free fall—orbiting objects are constantly falling toward Earth, but their forward motion keeps them in orbit. Since everything falls together, there's no force pushing against us, creating the sensation of weightlessness.

Why do we have friction?

We have friction because surfaces are not perfectly smooth—microscopic bumps and irregularities interlock and resist motion. Friction helps us walk, grip objects, and control motion, making it essential for many everyday activities.