Vocab
the vector sum of two or more vectors
Which method of finding vector resultants is more accurate and why?
analytical is more accurate than graphical because of accuracy of instrument, human error
a piece of a vector that points in either the vertical or the horizontal direction; every 2-d vector can be expressed as a sum of two vertical and horizontal vector component
component
CCW
What is the y-component of an acceleration of an object experiencing projectile motion?
-9.8 m/s2
the method of determining the magnitude and direction of a resultant vector using the Pythagorean theorem and trigonometric identities
analytical method
the path of a projectile through the air
trajectory
a force that opposes the motion of two systems that are in contact and moving relative to one another
kinetic friction
What is the global angle of 30 degrees South of West?
180+30= 210 degrees
What angle of a projectile would result in a 0 magnitude range?
0 or 90
drawing vectors on a graph to add them using the head-to-tail method
graphical method
the maximum horizontal distance that a projectile travels
range
a force that opposes the motion of two systems that are in contact and are not moving relative to one another
static friction
When during the trajectory of a projectile does the velocity = 0?
at the highest point, maximum height
if an object sits on an incline plane what is typically equal in magnitude to the component of the weight perpendicular to the plane?
Normal force
a method of adding vectors in which the tail of each vector is placed at the head of the previous vector
head-to-tail method
What formula would you use to find the x-component of a vector A (when an angle is given relative to the horizontal)
Ax= A cos (theta)
A large box is pushed across a carpet floor, if the weight of the box and the applied force is known what formula would you use to find the coefficient of friction between the carpet and the box.
Friction force divided by normal force
What formula would you use to find angle theta when given the vector components
theta =inverse tangent (Ry/Rx)
A rock is thrown from a ravine at the same time as an egg falls from a tree into the ravine. If the starting height is the same which item will land first?
same time
Consider 6 vectors of 2 cm each, joined from head to tail making a hexagon. What would be the magnitude of the addition of these vectors?
0 cm. when vectors from a closed loop their vector sum is zero
A person attempts to cross a river in a straight line by navigating a boat at 10 m/s. If the river flows at 5 m/s from left to right, what would the magnitude of the boats resultant velocity be?
Vr= square root of Vx2+Vy2
Vr= 11.18 m/s
A snowboarder with a mass of 82 kg is accelerating downhill. If the coefficient of kinetic friction between the board and snow is 0.07 what is the friction force?
56.252 N
A stone is thrown horizontally at 8.0 m/s from a cliff 80m high. How far from the base of the cliff will the stone strike the ground?
32 meters
The component of weight parallel to an inclined plane of an object resting on an incline that makes an angle of 70 degrees with the horizontal is 100 N. What is the objects mass?
10.86 kg