PROJECTILES
THE RANGE IS THE HORIZONTAL DISPLACEMENT THAT THE PROJECTILE WILL TRAVEL BEFORE HITTING THE GROUND
FOR AN ANGLED PROJECTILE, WHICH PRODUCES THE FURTHEST RANGE?
45 DEGREES PRODUCES THE LARGEST RANGE.
>45 DEG SPENDS LESS TIME IN AIR
<45 DEG SPENDS MORE TIME IN AIR
WHAT IS THE DIFFERENCE BETWEEN A SCALAR AND A VECTOR.
A SCALAR IS MAGNITUDE AND NO DIRECTION
A VECTOR IS BOTH MAGNITUDE AND DIRECTION
A STONE IS THROWN HORIZONTALLY AT A SPEED OF 20M/S FROM THE TOP OF A CLIFF 80M HIGH.
HOW LONG DID IT TAKE FOR THE STONE TO REACH THE GROUND?
THE STONE TOOK 4.04S TO REACH THE GROUND.
WHAT DOES THE WORD "PARABOLIC TRAJECTORY" MEAN?
PARABOLIC-CURVED
TRAJECTORY-PATH
PARABOLIC TRAJECTORY-CURVED PATH.
IF I LAUNCH A PROJECTILE AT 30 DEG WHAT OTHER ANGLE WILL PRODUCE THE SAME RANGE?
THESE ARE COMPLEMENTARY ANGLES
ANY 2 DEGREES THAT ADD UP TO 90DEG PRODUCE THE SAME RANGE.
THE OTHER ANGLE WILL BE 60DEG.
WHAT IS THE SYMBOL WE USE TO DRAW VECTORS?
WE USE AN ARROW TIPPED LINE TO SHOW VECTOR MAGNITUDE AND DIRECTION.
A STONE IS THROWN HORIZONTALLY AT A SPEED OF 20M/S FROM THE TOP OF A CLIFF 80M HIGH.
HOW FAR DID THE STONE TRAVEL FROM THE BASE OF THE CLIFF?
THE STONE TRAVELLED 80.8M FROM THE BASE OF THE CLIFF.
WHAT IS THE INITIAL VERTICAL VELOCITY OF A HORIZONTAL PROJECTILE?
THE VERTICAL VELOCITY IS ALWAYS 0M/S INITIALLY AND GETS FASTER THE LONGER THAT IT IS IN THE AIR.
WHAT TWO THINGS ARE AFFECTED BY THE ANGLE OF A LAUNCHED PROJECTILE?
THE MAXIMUM HEIGHT IS AFFECTED BY THE Y COMPONENT OF THE ANGLE
THE MAXIMUM RANGE IS AFFECTED BY THE X COMPONENT OF THE ANGLE.
WHAT IS THE SUM OF TWO OR MORE VECTORS CALLED?
THE SUM OF TWO OR MORE VECTORS ADDED TIP-TO-TAIL IS CALLED THE RESULTANT VECTOR.
AN AIRPLANE FLYING NORTH AT 230KM/HR EXPERIENCES A TAILWIND OF 30KM/HR.
WHAT IS THE RESULTANT VELOCITY OF THE AIRPLANE?
230KM/HR N +30KM/HR N=260KM/HR N
HOW DO THE HORIZONTAL AND VERTICAL MOTION OF A PROJECTILE AFFECT EACH OTHER?
THEY DON'T!
THE HORIZONTAL AND VERTICAL MOTIONS ARE INDEPENDENT OF EACH OTHER!
IF IT TAKES 3 SECONDS FOR THE ANGLED PROJECTILE TO REACH ITS MAX HEIGHT HOW LONG DID IT TAKE FROM LAUNCH BACK DOWN TO THE GROUND?
IT TOOK 6 SECONDS.
MAXIMUM HEIGHT IS HALF THE TIME IT TAKES FOR THE FULL TRAJECTORY.
WHAT IS THE METHOD THAT IS USED WHEN ADDING VECTORS REGARDLESS OF DIRECTION?
VECTORS ARE ALWAYS ADDED TIP-TO-TAIL REGARDLESS OF DIRECTION.
WHILE FLYING EAST AT 120KM/HR AND AIRPLANE EXPERIENCES A NORTHWARD WIND OF 45KM/HR. WHAT IS THE RESULATANT VELOCITY OF THE AIRPLANE?
MAGNITUDE AND DIRECTION!
THE RESULTANT IS FOUND BY ADDING TIP TO TAIL AND USING PYTHAGOREAN THEOREM.
SQRT(1202+452)=128.16KM/HR
THE DIRECTION IS FOUND BY USING THE INVERSE TRIG FUNCTIONS
TAN-1(OPP/ADJ)=TAN-1(45/120)=20.6DEG N OF E
IF I WANT TO INCREASE THE AMOUNT OF TIME THAT A PROJECTILE IS IN THE AIR, WHAT CAN I DO?
IF I LAUNCH A PROJECTILE WITH AN ANGLE OF 90DEG STRAIGHT UP AT 50M/S HOW FAST WILL IT BE MOVING RIGHT BEFORE HITTING THE GROUND?
A PROJECTILE LAUNCHED STRAIGHT UP WILL LOSE ITS VELOCITY ON THE WAY UP AND THEN GAIN VELOCITY EQUAL TO THE STARTING VELOCITY ON THE WAY DOWN.
RIGHT BEFORE IT HITS THE GROUND IT WILL BE MOVING AT 50M/S.
WHAT IS THE DIFFERENCE BETWEEN TOTAL DISPLACEMENT VS TOTAL DISTANCE
(MORE THAN JUST VECTOR AND SCALAR)
TOTAL DISPLACEMENT(VECTOR)-IS FROM END TO START AND KEEPS TRACK OF DIRECTION OF WHERE I WAS TO WHERE I ENDED.
TOTAL DISTANCE(SCALAR)-TELLS ME HOW MUCH DISTANCE I COVERED BUT NOT WHICH WAY I WENT.
A ROCKET IS LAUNCHED AT ANGLE OF 18DEG S OF W WITH AN ACCELERATION OF 120M/S2. WHAT ARE THE COMPONENTS OF THE ROCKET'S ACCELERATION?
AX=118COS(18)=112.22M/S2 W
AY=118SIN(18)=36.46M/S2 S