Aerodynamics

Aerodynamics is a branch in physics studying the motion of an object and its interaction with air.  The picture to the left shows the vortex created by an airplane due to the difference in pressure. A red smoke is usually used as an indicator to study the motion of air. The 2 sub-topics in aerodynamics fluid dynamics and gas dynamics.

The glider depends heavily on the density of its medium. In air for example, the glider will glider further in a higher air density environment, because the more air particles the wings catch, the further it will glide.  The aircraft's resistance to the airflow (drag) depends on the shape of the fuselage and flying surfaces. An aircraft that is intended to fly fast has a thinner and different wing profile than one that is intended to fly slower. That's why many aircraft change their wings' profiles on landing approach by lowering the flaps located at the wings' trailing edge and the slats at the leading edge in order to keep enough lifting force during the much lower landing speed.

5 projectile motions, questions, and answers

Homework

Drawing the graphs

Graph #1  d/t

v/t

Graph #2 D/t

v/t

Graph #3v/t d/t

Graph #4v/t

d/t

a/t

Graph #5d/t

v/t

Walking the graphs

Again, this probably was the most effective way to start a new chapter :)
This lab helped me understand the real motion behind the science of motion.
Probably the most fundamental knowledge that is important to later studies.

I definitely learned a lot from this activity, from how a motion sensor works, to how to plot a graph with the change in speed and distance.
I personally think these activities help me understand the physics behind the math, and its a awesome way to understand the concept before applying them.

Looking forward to more labs!!!!!!!!!!!

Right Hand Rules.

Based on Oersted's principals of current and magnetic field, three right hand rules can be applied to help us understand some concepts. Firstly, we must understand that all right-hand rules are based on the concept of conventional current, which is the movement of protons from positive to negative. If electron flow is considered, the same results can be obtained by using the left-hand rule.

Right-hand Rule #1



 Right-hand rule number one states the relationship between the direction of current flow and the direction of the magnetic field generated as a result. Given either one of the variables, the other can be determined.
Taking the above diagram as example, the direction of the thumb pointing at represents the direction of the current. The direction of the fingers holding the conductor therefore represents the direction of the magnetic field.

Right-hand Rule #2
 
 

The right-hand rule explains the concept when a conductor is coiled around a metal, magnetizing the metal.  In this case, the fingers will point to the direction of current flow, and the thumb will reveal the north of the magnet.

Concept Map + must knows for electricity

 

This is the concept map  we created to summarize this entire unit :) Below lists some of the most important terms you must know for this unit.

Series Circuit - a complete circuit with all the loads/resistors connected in a                                                   continuous connection, if one load/point is removed or damaged, the entire circuit fails.

Electron Flow - the flow of electrons (-) in a circuit from the negative terminal to the positive terminal.

Conventional Current - the flow of protons (+) from the positive terminal to the negative terminal.

Coulombs (Q) - the measurement of the number of electrons, in the unit of C

Current (I)- the measurement of electron flow using an ammeter in the unit of A (Amperes)

in the formula I= Q/t

Voltage(V) - a measurement of electric potential energy between two points in the unit of V (Volts). This        is calculated by the formula V= E/Q, where E is the energy required to increase the electric potential of a charge, Q.

Resistance (R) - is the measurement of the opposition to flow, measure in the unit , this is calculated by the formula R = V/I.

Ohm's Law - this law presents a significant relationship between resistance, voltage, and current. Voltage and current displays a linear relationship to each other, and the slope remains constant in the same graph. The slope is the resistance of a circuit, which do not change under variations of voltage/current.

Kirchhoff's current law - The total amount of current into a junction point of a circuit equals the total current that flows out of that same junction.

Kirchhoff's voltage law -  The total of all electrical potential decreases in any complete circuit loop is equal to any potential increases in that circuit loop.

Power - the rate which work is being down, can be calculated by the equation P = IV