DYNAMICS by Sukesh Kamath

The relationship F = ma ( Newtons Second Law )

sukeshkamath — 2016-01-25 05:28:28 UTC

For a body of constant mass, its acceleration is directly proportional to the resultant force applied to it.

Here, F describes the force acting, m is the mass of the object, and a is its acceleration, the change in its motion.
Like motion, force has both a value or "strength", and a direction in which it acts.

We commonly think of "acceleration" as a speeding up, but in physics it can also include a slowing down ("deceleration") as well as a change in direction.

In the metric system, the unit of force is called a Newton, whose abbreviation is "N".

A Newton is equal
to 1 kg•m/s².
http://www.mrmont.com/games/secondlawlaunch.html

The larger the force is, the larger the acceleration

sukeshkamath — 2016-01-25 05:30:46 UTC

or an equal force, a larger mass must have a smalleracceleration, and vice versa

sukeshkamath — 2016-01-25 05:31:55 UTC

A larger mass has greater inertia than a smaller mass.

This is one way that we can measure an object's mass.

Newton's First Law)

sukeshkamath — 2016-01-25 05:36:48 UTC

An object will remain at rest or in a state of uniform motion unless it is acted by a resultant force.

An object will never change its speed or direction unless something comes along and forces it to do so.

http://www.mrmont.com/games/docktherocket2.html

Inertia

sukeshkamath — 2016-01-25 05:40:58 UTC

An object's resistance to changes in motion is known as inertia

Every material object has inertia and the amount of matter present in the object.

Mass

sukeshkamath — 2016-01-25 23:57:27 UTC

Mass is the quantity of matter in an object and is independent of the body’s surroundings and method used to measure it (scalar quantity)

Inertial mass mi specifies how much inertia an object has. It is a measure of the response of an object to an external force.

Mass is measured in Kilogram.
Mass Always Stays the Same!!

Weight

sukeshkamath — 2016-01-26 01:50:15 UTC

The weight of an object is defined as the gravitational force acting on the object, and is dependent on the mass of the body.

The acceleration due to gravity (or acceleration of free-fall, usually denoted by g) is taken as the constant for all bodies, although it varies slightly from place to place.

We can calculate the weight of an object from its mass by the equation W = mg, where W=weight, m=mass and g=acceleration of free fall.

http://www.mrmont.com/games/scale.html

One Newton

sukeshkamath — 2016-01-26 01:54:50 UTC

One Newton is the force required to accelerate a mass of 1 kg at 1 meter per second square.

In the SI unit system, force is measured in Newtons

Newton's Third law

sukeshkamath — 2016-01-26 02:02:11 UTC

when two bodies interact, the forces they exert on each other are equal in magnitude and opposite in direction.

You are familiar with this law from striking an object with your hand: the object moves as a result, but your hand also feels a force, and bounces back

Two forces which make up this law have the following characteristics.

They act on different objects
Theya are equal in magnitude.
they are opposite in direction
they are forces of the same type.
http://www.mrmont.com/games/catchinspace.html

Linear momentum

sukeshkamath — 2016-01-26 02:09:09 UTC

Linear momentum, P, is defined as the mass, m, of an object multiplied by its velocity, v, so:

P = mv

Units: kgms^-1 or Ns

Defining Force in terms of momentum.

sukeshkamath — 2016-01-26 02:12:06 UTC

Force can be defined as the rate of change of momentum.

Free Fall

sukeshkamath — 2016-01-26 02:20:19 UTC

A free falling object is an object that is falling under the sole influence of gravity. Any object that is being acted upon only by the force of gravity is said to be in a state of free fall.

Terminal velocity

sukeshkamath — 2016-01-26 02:22:54 UTC

Terminal velocity is the highest velocityattainable by an object as it falls through air. It occurs once the drag force (F_d) and buoyancy equals the downward force of gravity (F_G) acting on the object. Since the net force on the object is zero, the object has zero acceleration.

When an object is dropped, we can identify three stages before it hits the ground:

At the start, the object accelerates downwards because of its weight. There is no air resistance. There is a resultant force acting downwards.
As it gains speed, the object's weight stays the same, but the air resistance on it increases. There is a resultant force acting downwards.
Eventually, the object's weight is balanced by the air resistance. There is no resultant force and the object reaches a steady speed, called the terminal velocity.

For simulation :http://www.waowen.screaming.net/revision/force&motion/skydiver.htm

http://lab.concord.org/embeddable.html#interactives/inquiry-space/parachute.json

sukeshkamath — 2016-01-28 05:46:57 UTC