Gravity Component

Gravitropism: Plant Responses to Gravity Higher plants sense gravity using statocytes, cells found near the vascular tissue in shoots, and in the root cap columella in roots. Statocytes contain starch-filled organelles called statoliths. The statoliths settle, or sediment, at the bottom of the statocyte in the direction of gravity. Statolith sedimentation triggers a signaling cascade, resulting in the asymmetrical distribution of the plant hormone auxin across root and shoot tips. This...

The center of gravity (COG) of an object is the point where the object's total weight is considered to be concentrated. Knowing the location of the center of gravity is useful when predicting the behavior of a moving object or designing static structures. In a uniform gravitational field, the center of gravity is similar to the center of mass (COM); yet, these two points can be positioned differently. For example, the Moon's center of mass lies very close to its geometric center, but its center...

Gravitation is one of the four fundamental forces in nature. The force between objects on Earth and Earth itself is called gravity. Like other forces, gravity does work on an object if it displaces it toward the Earth's center. In this case, the work done by gravity is said to be positive. If an external force acts on the object against the pull of gravity and manages to lift it away from the Earth's center, work is done against gravity. In this case, the net work done is said to be negative.

Newton's second law is closely related to his first law of motion. It mathematically gives the cause-and-effect relationship between force and changes in motion. Newton's second law is quantitative and is used extensively to calculate what happens in situations involving a force. All external forces acting on a system add together to produce a net force Fnet. A larger net external force produces a larger acceleration. This acceleration is directly proportional to, and in the same direction as,...

The gravitational acceleration of an object near the Earth's surface is called the acceleration due to gravity. It can be measured by conducting simple experiments on Earth. However, such an experiment is impossible to conduct on the surface of other planets. Astronomical observations are thus used to measure the acceleration due to gravity on other planets. This can be determined by observing the effect of a planet's gravity on objects close to it. The crucial factor that helps in this...