Scalar vs Vector

Scalar: without direction. For example, length, time, mass.

Vector: with direction. For example, displacement, acceleration, force.
Scalar: without direction. For example, length, time, mass.
Vector: with direction. For example, displacement, acceleration, force.
AxisVector components
VectorVector components
Gravity components on slope
Speed vs Velocity

Speed: scalar, no direction, rate of change in distance.

Velocity: vector, has direction, rate of change in displacement.
Speed: scalar, no direction, rate of change in distance.
Velocity: vector, has direction, rate of change in displacement.
Instantaenous speed vs Instantaneous velocity
SPEED: Instantaneous speed is the speed at an instant (infinitesimal time interval). Instantaneous speed equals instantaneous velocity in magnitude.
VELOCITY: Instantaneous velocity is the velocity at an instant (infinitesimal time interval). Instantaneous velocity has a direction, instantaneous speed does not. The direction of instantaneous velocity is tangent to the path at that point.
Add the following vectors and determine the resultant.:
5.0 m/s, 45 deg and 2.5 m/s, 135 deg
5.0 m/s, 45 deg+ 2.5 m/s, 135 deg= 5.59 m/s, 71.6 deg
MAGNITUDE: 5^{2} + 2.5^{2} = 31.25 whose square root is 5.59
DIRECTION: The xcomponent of the resultant vector is 5cos(45) + 2.5cos(135) = 1.77 and the ycomponent of the resultant vector is 5sin(45) + 2.5sin(135) = 5.30. Then, you take the tan^1(5.30/1.77) which is 71.6 degrees.
Add the following vectors and determine the resultant.
3.0 m/s, 45 deg and 5.0 m/s, 135 deg and 2.0 m/s, 60 deg
MAGNITUDE:
x component: 3cos(45) + 5cos(135) + 2cos(60) = 0.414
y component: 3sin(45) + 5sin(45) + 2sin(60) = 7.389
Finding the square root of the sums of the components: 7.401
DIRECTION: tan1(7.389/0.414) = 86.79 + 180 = 93.21.
What are the FOUR equations at constant acceleration?
What happens to the speed at terminal velocity?
At terminal velocity, weight = friction, so the net force is 0. Thus, the acceleration is 0. So, the speed stays constant at terminal velocity.
What will happen to the acceleration with air resistance?

The acceleration is no longer constant  it will decrease with time until it gets to zero at terminal velocity.

When there's air resistance, the acceleration will decrease because the force (weight  resistance) is decreasing due to increasing resistance or friction at higher speeds.
The acceleration is no longer constant  it will decrease with time until it gets to zero at terminal velocity.
When there's air resistance, the acceleration will decrease because the force (weight  resistance) is decreasing due to increasing resistance or friction at higher speeds.
What do you use to find the time that a projectile is in air?
Use the vertical component only.
How do you find how far a projectile traveled?
First get the time in the air by the vertical component. Then use the horizontal component's speed * time of flight
Equation for uniform circular motion
A pool ball leaves a 0.60meter high table with an initial horizontal velocity of 2.4 m/s. Predict the time required for the pool ball to fall to the ground and the horizontal distance between the table's edge and the ball's landing location.
y = 0.60 m = (0 m/s)•t + 0.5•(9.8 m/s/s)•t^{2}
t = 0.350 s
x = (2.4 m/s)•(0.3499 s) + 0.5•(0 m/s/s)•(0.3499 s)^{2}
x = 0.84 m