Biomechanics exam

Momentum

The quantity of motion an object possesses, calculated as the product of its mass and velocity. It is a vector quantity, meaning it has both magnitude and direction.

Kinetic Energy

The energy that an object has due to its motion, which depends on its mass and speed. It is calculated using the formula $KE = \frac{1}{2}mv^2$, where $m$ is mass and $v$ is velocity.

Potential Energy

The energy stored in an object due to its position in a gravitational field or its configuration. For example, an object raised above the ground has gravitational potential energy, which can be calculated as $PE = mgh$, where $m$ is mass, $g$ is the acceleration due to gravity, and $h$ is the height.

Work

The process of energy transfer that occurs when a force is applied to an object and the object moves in the direction of the force. It is quantified as the product of force and displacement, mathematically expressed as $W = F \times d \times \text{cos}(\theta)$, where $\theta$ is the angle between the force and the direction of motion.

Power

The rate at which work is done or energy is transferred over time. It is measured in watts (W) and can be calculated using the formula $P = \frac{W}{t}$, where $W$ is work done and $t$ is the time taken.

Newton's First Law

A fundamental principle stating that an object at rest will remain at rest, and an object in motion will continue moving at a constant velocity in a straight line, unless acted upon by a net external force. This law is also known as the law of inertia.

Newton's Second Law

A principle that describes the relationship between the force applied to an object and its resulting acceleration. It states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass, expressed as $F = ma$.

Newton's Third Law

A principle stating that for every action, there is an equal and opposite reaction. This means that forces always come in pairs: when one body exerts a force on a second body, the second body exerts an equal and opposite force on the first.

Friction

The resistive force that opposes the relative motion of two surfaces in contact. Friction acts parallel to the surfaces and is dependent on the nature of the surfaces and the normal force pressing them together.

Centripetal Force

The net force required to make an object move in a circular path, directed towards the center of the circle around which the object is moving. This force can be provided by gravity, tension, friction, or any combination of these forces.