Force, Mass & Acceleration: Newton's Second Law of Motion
Newton's Second Law: Force, Velocity and Acceleration. Duration: class periods. Essential Question: What are the relation- ships between force, mass, and. Velocity as function of initial velocity [v0], acceleration[a] and time[t]: with artificial rotation like spinning a ball or any type of rotation not related to gravity. Time is the medium for both velocity and acceleration to occur. Another relationship between the two is that when velocity is constant.
It should be noted that any bold letters are vectors meaning that they have magnitude and direction.
So a change in momentum corresponds to a change in kinetic energy. This is the essence of Newton's second law: An acceleration just represents this change in momentum for an object that has a constant mass. The units newtons and joules can be connected directly. For a mass under a constant force, F. So moving an object a distance x with a force F changes the kinetic energy in a mathematically direct fashion.
This description of forces, masses, and energies is a little simplistic.
Newton's Second Law
Wikipedia's article has some mathematical rigor but both are very informative. I hope this answered your question and piqued your interest, Mark Follow-Up 1: Kinetic Energy is Relative Q: Kinetic energy is entirely relative.
For a platform-based observer, the car has 50kJ of kinetic energy 0. Thus the car has no kinetic energy 0.
Newton's Second Law
If the driver were to hit the brakes a very funny thing happens. To the platform-based observer the car decelerates and stops: But for the ground-based observer the exact opposite happens!
The car accelerates in the direction of the moving platform and some of the kinetic energy of the platform is transfered to the car. That transfer of energy creates heat and heats up the brakes. So kinetic energy along with maaany other things is reference-frame dependent. Galileo's experiments showed that all bodies accelerate at the same rate regardless of size or mass. Newton also critiqued and expanded on the work of Rene Descartes, who also published a set of laws of nature intwo years after Newton was born.
Displacement, velocity, acceleration
Descartes' laws are very similar to Newton's first law of motion. Acceleration and velocity Newton's second law says that when a constant force acts on a massive body, it causes it to accelerate, i.
In the simplest case, a force applied to an object at rest causes it to accelerate in the direction of the force. However, if the object is already in motion, or if this situation is viewed from a moving inertial reference frame, that body might appear to speed up, slow down, or change direction depending on the direction of the force and the directions that the object and reference frame are moving relative to each other.Position, Velocity, Acceleration using Derivatives
The bold letters F and a in the equation indicate that force and acceleration are vector quantities, which means they have both magnitude and direction. The force can be a single force or it can be the combination of more than one force.
- How are acceleration, time and velocity related?
It is rather difficult to imagine applying a constant force to a body for an indefinite length of time. In most cases, forces can only be applied for a limited time, producing what is called impulse. For a massive body moving in an inertial reference frame without any other forces such as friction acting on it, a certain impulse will cause a certain change in its velocity.
The body might speed up, slow down or change direction, after which, the body will continue moving at a new constant velocity unless, of course, the impulse causes the body to stop. There is one situation, however, in which we do encounter a constant force — the force due to gravitational acceleration, which causes massive bodies to exert a downward force on the Earth.
Notice that in this case, F and g are not conventionally written as vectors, because they are always pointing in the same direction, down.