They Taught Us to Move Fast, but Also to Stay

Kinetic energy is the ability of an object in motion to do work or enact change. It can take on many forms. For instance, water flowing down a waterfall has kinetic energy. In biological systems, particles of light travel and are absorbed by plants to create chemical energy. Animals consume the chemical energy and give off molecules that carry their scent through the air. They also generate kinetic energy when they run away from predators. Entire systems also possess kinetic energy, like the...

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,...

Newton's second law of motion applies to bodies moving under the same acceleration. For example, when a baggage tractor pulls luggage carts, each cart moves at the same acceleration as that of the tractor.

The total momentum of a system consisting of N interacting objects is constant in time or is conserved. A system must meet two requirements for its momentum to be conserved:

The motion of an object in space, such as a drone flying through the air, can be described mathematically using a position vector, denoted r(t), which specifies the object's location at any given time t. Analyzing the motion of the drone involves examining how this position vector changes over time.The average velocity over a time interval is obtained by dividing the change in position by the duration of the interval. As the interval becomes infinitesimally small, this average velocity...

The second kinematic equation expresses the final position of an object in terms of its initial position, the distance traveled with the initial constant velocity, and the distance traveled due to a change in velocity. Similar to the first kinematic equation, this equation is also only valid when the acceleration is constant throughout the motion of an object.
Suppose a car merges into freeway traffic on a 200 m long ramp. If its initial velocity is 10 m/s and it accelerates at 2 m/s2, then the...