THE LANGUAGE OF PHYSICS

ACCELERATION= a a= (v f -v i )/t v f - final velocity, v i - initial velocity UNITS ARE m/s 2 CONSTANT a NEGATIVE a POSITIVE a a t CONSTANT V a t a t a t

VELOCITY= v v= d/t= units are m/s CONSTANT a NEGATIVE a POSITIVE a v t CONSTANT V v t v t v t

DISTANCE- d How far you have traveled Measured in m, km, miles, cm CONSTANT a NEGATIVE a POSITIVE a d t CONSTANT V d t d t d t d t Not Moving

SCIENTIFIC METHOD PROBLEM -What is the question to be studied HYPOTHESIS If ____ is the answer then the data will show _______ because. CONCLUSION How the data relates to the hypothesis, does the trend match or not. DATA Charts and graphs used to identify a trend in the data PROCEDURE How you will prove your point. Be aware of safety. QUESTION Based on the data what would be the next logical question to study. CONTROLS- What would happen if nothing was changed VARIABLES- Things that Could alter the results INDEPENDENT- Changed by the scientist (x axis) DEPENDENT- The result of the change, what is measured. X axis TESTABLE- Must be

FREE FALL Falling object only being effected by gravity v v = at d v = v i + 1/2at 2 AIR RESISTANCE- upward Force that reduces the effects of gravity in free fall GRAVITY- down force created by the earth, causes acceleration in free fall TERMINAL VELOCITY when air resistance has built up the ability to stop acceleration g= 9.8 m/s2 ACC caused by gravity ALWAYS

KINEMATIC EQUATIONS Use Equation containing known and one unknown variable to find What I have- variables given in problem What I need the question is asking for this variable in this unit Formula- How will I use the known to solve for the unknown d= v i t + ½ at 2 d= (v i + v f )/ 2 t v f 2 = v i 2 + 2ad v f = v i + at

RELATIVE MOTION Motion based on the position (REFERENCE FRAME) of the observer. SEES CAR AT 60 km/h and grandpa is moving very slow SEES CAR AT 49 km/h and runner at 11 km/h SEES RUNNER AT 60 km/hr and grampa at 49 km/hr

PROJECTILE MOTION Horizontal Speed is Constant Vertical Speed changes due to gravity 45 degree angle is most efficient 2 angles that equal 90 degrees produce the same landing point Launch angle is separated into vertical and horizontal components V i =V f v x = v*cos° (horizontal speed) v y = v*sin ° (vertical speed) d y (height)= ½*9.8*t 2 d v (distance)= v*t

LAW OF INERTIA Newton’s First Law of Motion Inertia- the ability of an object to not be changed by force. An object will remain at rest or in motion unless a force (greater than its inertia) acts upon it. Weight in Newton's (inertia)= Kilograms X 9.8 m/s 2 22kg x 9.8 m/s2 = 215 N (inertia) Conversions 10lbs x 2.2= 22Kg

LAW OF ACCELERATION 2 nd Law of Motion Once inertia is overcome the change in an object will be proportional to the force applied to it Motion occurs or changes when forces on an object become unbalanced. Force (N)= mass (Kg) x Acceleration (m/s 2 )

LAW OF ACTION REACTION Newton's 3 rd law of motion. For every action force there is an EQUAL AND OPPOSITE reaction force. Example when two cars hit the force they experience is the same, but the car with less inertia tends to take more damage and bounce off farther.

WORK AND POWER Work is the application of force which causes movement, if there is no movement there is no work. Power how quickly work can be done. If mass is = than taller Did more work. If work is equal than faster has more power.

ANGULAR MOTION Theta is the symbol for angular distance, similar to meter for linear distance. It is the arc length/radius. The unit for distance is a radian The term alpha means angular acceleration The units are rads/s 2 similar to m/s 2 in linear acceleration. The term omega means angular speed. The units are rads/s similair to m/s in linear speed.. i f Satellites stay in orbit using angular speed to fight the pull of gravity, the lower the orbit the faster the speed to stay balanced

WORK AND POWER The ability to move an object using force divided by the time it takes to get it done.

MOMENTUM Force created by the size and speed of the object. Force you hit with. Momentum is conserved meaning the total momentum in a collision does not change, the amount in each object does

ENERGY KE= 1/2mv 2 CONSERVATION OF ENERGY means that the total energy in a closed system does not change, PE + KE always remains constant. MAX PE = MAX KE Potential- position, Kinetic- motion Unit= Joules