April Estrada- Speed, Velocity, and Acceleration

Definitions: 

Speed- The speed of an object is how much distance it travels per unit of time. 
Velocity- The velocity of an object is its speed and direction of travel.
Acceleration- Is the rate of change of an objects velocity.

Summary:
   When an object is moving it is in motion, and when it's not moving it is at rest. For example to move your car from on side of the parking lot to the other the car must travel over a distance. You can measure the amount of time it takes the car to travel over this distance. (MOTION) The SPEED of the car is how much distance it travels per unit of time. You can measure speed in meter per second (m/s). The average speed can be calculated: v=d/t (Speed= Distance traveled/ Time) -The speed and direction of an object together are called its VELOCITY. It has a constant velocity when an object is traveling at a constant speed in a constant direction.

   Newton's first law of motion states that any object will stay in equilibrium until an external force acts on the object to change its velocity. EQUILIBRIUM is applied when an object is at rest or is in motion at a constant velocity. INERTIA is the tendency of an object to maintain its state of uniform motion unless acted on by an external force. The inertia of an object makes the object stay in equilibrium until a (push or pull) acts on the object. The sum of all forces on an object is called the NET FORCE.

   The object is no longer in equilibrium once the net external force is not zero. It is said to be in accelerated motion. It's the same deal as an object is observed to have velocity when it has a change in position- an object is observed to have accelerated motion when it has a change on velocity. (ACCELERATION) Acceleration is measured in meters per second squared. (m/s2) The average acceleration (a) can be calculated using: a= Vf-Vi/t (Acceleration= Final Velocity- Initial Velocity/ Change in Time)  

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Chemistry 101

Trends In Periodic Table

Work, Paper, Efficiency

Maria Rodriguez

Work, Paper, Efficiency:

Work, is the enegy transferred by applying a force on an object over a distance. But when a work is a negative value. When the object is moving, it means that the force is acting in two opposite direction as it is moving. Which means that the force is taking energy away from the light.

Power, is the rate which work is done on a object. Machines are used to put work power to it, and you combined the machine together with the power, and it makes the machine work. Sometimes the machine can have an electrical occurance and it can cause a short circut and will eventually damage the machine.

Percent efficiency of a machine is the ratio of the work output to the work input. It explains how much energy the machine needs to work as a adpated to the energy.

characteristics of waves

a wave is a disturbance that carries energy through matter of space. a transverse wave is energy that is transmitted by an oscillation that is perpandicular to the direction the wave is moving. a longitudinal wave is energy transmitted by an oscillation parrallel to the direction the wave is moving. a harmonic wave is a wave in the shape of a sine function. the frequency is the number of complete oscillation a wave makes each second. period is the amount of time it takes for one oscillation. the wavelength is the distance from the top of a pulse to the top of the next pulse. the amplitude of a wave is the maximum displacement of a wave from its position of rest.


pulse wave                                     pulse train                                         harmonic wave




transverse harmonic wave                longitudinal harmonic wave

Don lesson 35

Machines and Classical Mechanics

There are four known types of force in the universe: gravitational, electromagnetic, weak nuclear, and strong nuclear. This was the order in which the forces were identified, and the number of machines that use each force descends in the same order. The essay that follows will make little or no reference to nuclear-powered machines. Somewhat more attention will be paid to electrical machines; however, to trace in detail the development of forces.A machine can be many thing for a pulley to now and days technology like computers cars planes and levers even phones we use machine everyday in our everyday lives.

Instead, the machines presented for consideration here depend purely on gravitational force and the types of force explainable purely in a gravitational framework. This is the realm of classical physics, a term used to describe the studies of physicists from the time of Galileo Galilei (1564-1642) to the end of the nineteenth century. During this era, physicists were primarily concerned with large-scale interactions that were easily comprehended by the senses, as opposed to the atomic behaviors that have become the subject of modern physics.

Late in the classical era, the Scottish physicist James Clerk Maxwell (1831-1879)—building on the work of many distinguished predecessors—identified electromagnetic force. For most of the period, however, the focus was on gravitational force and mechanics, or the study of matter, motion, and forces. Likewise, the majority of machines invented and built during most of the classical period worked according to the mechanical principles of plain gravitational force.

This was even true to some extent with the steam engine, first developed late in the seventeenth century and brought to fruition by Scotland's James Watt (1736-1819.) Yet the steam engine, though it involved ordinary mechanical processes in part, represented a new type of machine, which used thermal energy. This is also true of the internal-combustion engine; yet both steam-and gas-powered engines to some extent borrowed the structure of the hydraulic press, one of the three basic types of machine. Then came the development of electronic power, thanks to Thomas Edison (1847-1931) and others, and machines became increasingly divorced from basic mechanical laws.

A common trait runs through all forms of machinery: mechanical advantage, or the ratio of force output to force input. In the case of the lever, a simple machine that will be discussed in detail below, mechanical advantage is high. In some machines, however, mechanical advantage is actually less than 1, meaning that the resulting force is less than the applied force.

This does not necessarily mean that the machine itself has a flaw; on the contrary, it can mean that the machine has a different purpose than that of a lever. One example of this is the screw: a screw with a high mechanical advantage—that is, one that rewarded the user's input of effort by yielding an equal or greater output—would be useless. In this case, mechanical advantage could only be achieved if the screw backed out from the hole in which it had been placed, and that is clearly not the purpose of a screw.

                                               Simple machine machanical advantge





                                       this lesson is about inersha and the diffrent force there
                                       are.
                        



                                   

Forces 101

When talking about Force you can also refer to Newton's second law of motion which states that if a net force acts on an object, then the object accelerates proportional to the net force and inversely proportional to the mass of the object being accelerated. Terms were given within the chapter such as Mass which is a measure of the inertia of an object. The Normal Force is the perpindicular force of a surface pushing back on an object when the object pushes against the surface. Friction is a force on an object when the object slides or tries to slide on a surface or through a medium such as air or water. Centripetal Force is a force pulling an object toward the center of a circular path as it travels around a circle. Gravity is the force that causes objectsto fall to the ground. The Acceleration Due To Gravity (g) is a constant acceleration at which any object of any weight falls to the ground when no other force except gravity is acting on it. Weight is the force of gravity on an object.

Newton's second law of motion (F=ma); Force= Mass x Acceleration

For this equation, when mass is measured in kilograms (kg) and acceleration is measured in m/s (squared), then net force (F) is calculated in newtons (N). using this equation, you should be able to see that the acceleration is always in the direction of the net force. There are other forces that can act upon an object. the Normal force is the perpendicular force of a surface, such as the ground, pushing back on an object pushes against the surface. A ball falling from the top of a building is also an example of a force that acts on an object causing it to accelerate.

The value for the acceleration due to gravity is g=9.8m/s (squared)