List the three (3) equations used in this chapter.
d = d o + v o ·t + ½ a·t 2
List the three (3) equations used in this chapter. d = d o + v o ·t + ½ a·t 2 v = v o + a·t
List the three (3) equations used in this chapter. d = d o + v o ·t + ½ a·t 2 v = v o + a·t a = (Δv) / t = (v – v o ) / t
Record the meaning of each variable.
d o = initial position
Record the meaning of each variable. d o = initial position d = current (or final) position
Record the meaning of each variable. d o = initial position d = current (or final) position v o = initial velocity
Record the meaning of each variable. d o = initial position d = current (or final) position v o = initial velocity v = current (or final) velocity
Define the following.
Position – location related to reference point
Define the following. Position – location related to reference point Velocity – change in position per time
Define the following. Position – location related to reference point Velocity – change in position per time Acceleration – change in velocity per time
Which parts of your car can instantly cause acceleration? Explain each.
Acceleration =
Which parts of your car can instantly cause acceleration? Explain each. Acceleration = change in velocity
Which parts of your car can instantly cause acceleration? Explain each. Acceleration = change in velocity Gas – increases (changes) speed Brake – decreases (changes) speed
Consider a position-time graph (d-t)
Slope = velocity
Consider a position-time graph (d-t) Slope = velocity Y-int = initial position
Consider a position-time graph (d-t) Slope = velocity Y-int = initial position Flat line = no change in position (no motion)
Consider a position-time graph (d-t) Slope = velocity Y-int = initial position Flat line = no change in position (no motion) Line = constant change (constant velocity)
Consider a position-time graph (d-t) Slope = velocity Y-int = initial position Flat line = no change in position (no motion) Line = constant change (constant velocity) Curve = changing velocity (acceleration)
Consider a velocity-time graph (v-t)
Slope = acceleration
Consider a velocity-time graph (v-t) Slope = acceleration Y-int = initial velocity
Consider a velocity-time graph (v-t) Slope = acceleration Y-int = initial velocity Flat line = no change (constant velocity) (zero acceleration)
Consider a velocity-time graph (v-t) Slope = acceleration Y-int = initial velocity Flat line = no change (constant velocity) (zero acceleration) Line = constant change (constant accel)
What do all acceleration-time graphs in this class look like? Why?
Flat lines
What do all acceleration-time graphs in this class look like? Why? Flat lines All our accelerations will be constant (no change)
Explain how an object can slow down with a positive acceleration.
Negative velocity and positive accleration
Explain how an object can slow down with a positive acceleration. Negative velocity and positive accleration +velocity and +acceleration (speed up) +velocity and (-)acceleration (slow down) (-)velocity and +acceleration (slow down) (-)velocity and (-)acceleration (speed up)
What general rule can you follow to know if an object speeds up or slows down during acceleration?
Acceleration and velocity direction:
What general rule can you follow to know if an object speeds up or slows down during acceleration? Acceleration and velocity direction: Same sign = speed up Opposite sign = slow down
Write an equation for a dune buggy that starts at the origin and travels to the right at 5.0 m/s.
d = d o + v o ·t + ½ a·t 2
Write an equation for a dune buggy that starts at the origin and travels to the right at 5.0 m/s. d = d o + v o ·t + ½ a·t 2 d = 0 + (5m/s) t + ½ (0) t 2
Write an equation for a dune buggy that starts at the origin and travels to the right at 5.0 m/s. d = d o + v o ·t + ½ a·t 2 d = 0 + (5m/s) t + ½ (0) t 2 d = (5)t
Write an equation for a car that starts at the origin at rest and accelerates to the right at 6.0 m/s 2.
d = d o + v o ·t + ½ a·t 2
Write an equation for a car that starts at the origin at rest and accelerates to the right at 6.0 m/s 2. d = d o + v o ·t + ½ a·t 2 d = 0 + (0 m/s) t + ½ (6 m/s 2 ) t 2
Write an equation for a car that starts at the origin at rest and accelerates to the right at 6.0 m/s 2. d = d o + v o ·t + ½ a·t 2 d = 0 + (0 m/s) t + ½ (6 m/s 2 ) t 2 d = (3)t 2
Write a velocity equation for the previous fan car.
v f = v o + a·t
Write a velocity equation for the previous fan car. v f = v o + a·t v f = 0 m/s + (6.0 m/s 2 )·t
Write a velocity equation for the previous fan car. v f = v o + a·t v f = 0 m/s + (6.0 m/s 2 )·t v f = (6)t
Using the previous two questions, show how you could find out when they would meet?
Set both equations equal to each other
Using the previous two questions, show how you could find out when they would meet? Set both equations equal to each other (5) t = (0.5) t 2
Using the previous three questions, show how you could find out where they would meet?
Use the calculated time in either equation
13a) a = 0.75 m/s 2 13b) ∆d = 216 m 14a) V f = 10 m/s 14b) ∆d = 150 m 15) v 0 = 5 m/s 16) ∆d = 48 m 17) a = -125 m/s 2 (an answer of 25 m/s 2 means you forgot directions on your velocities) 18a) a = -2.5 m/s 2 18b) ∆d = 125 m
d-ta-tv-t This shape can appear anywhere along the y-axis
d-ta-tv-t This shape can appear anywhere along the y-axis
d-ta-tv-t This shape can appear anywhere along the y-axis
d-ta-tv-t This shape can appear anywhere along the y-axis
d (m ) t ( sec) A B C D E F G