Physics Mechanics

A pound is a unit of mass/weight. A pound of any substance weighs exactly the same as a pound of any other substance.

The formula rhoghA represents pressure (rhog*h) multiplied by area (A), which equals force. In the context of fluids, this is the buoyant force (Archimedes' principle).

Newton's Second Law defines force as the rate of change of momentum, which is (mv - mu) / time.

Thinking distance is the distance a vehicle travels while the driver reacts. Factors like tiredness, alcohol, or distractions affect the driver's reaction time, whereas brakes and tyres affect braking distance.

Work done is defined as the product of the force applied and the distance moved in the direction of the force.

Gravitational Potential Energy (GPE) = m × g × h, where m is mass, g is gravitational acceleration, and h is height. The formula asks for g × height to complete the equation.

Power is defined as the rate at which work is done, calculated as work divided by time.

The formula for Kinetic Energy is 0.5 * mass * velocity squared (0.5 * m * v^2).

Strain is defined as the ratio of the extension of a material to its original length.

Stress is defined as the force applied per unit cross-sectional area.

Stopping distance is the sum of the thinking distance (distance traveled during reaction time) and the braking distance.

Pressure is defined as the force applied perpendicular to the surface of an object per unit area over which that force is distributed.

The SI base units are mass (kg), length (m), time (s), current (A), temperature (K), amount of substance (mol), and luminous intensity (cd). Voltage is a derived unit (J/C or W/A).

According to the principle of moments, for an object to be in equilibrium, the sum of clockwise moments must equal the sum of anticlockwise moments.