relationship between time, displacement, velocity, acceleration. kinematic
Post on 21-Jan-2016
244 Views
Preview:
TRANSCRIPT
Kinematic
Relationship between time, displacement, velocity, acceleration.Kinematic Relationships between the variables (s, d, t)This is the scalar relationship between speed, distance, and time.
s = speedd = distancet = time
speed = distance / times = d / tA car traveled 300 miles in 10 hours, determine the speed of the car.
distance = 300 milestime = 10 hourss = distance / time = 300 miles / 10 hours = 30 miles / hr.Relationships between the variables (v, d, t)This is the vector relationship between velocity, displacement, and time.
v = velocityd = displacementt = timevelocity = displacement / time
A car traveled 300 miles north in 10 hours, determine the velocity of the car.
displacement = 300 milestime = 10 hours
Velocity = displacement / time = 300 miles / 10 hours = 30 miles / hr. north
Variations on the same equationspeed = distance / timedistance = speed timetime = distance / speed
velocity = displacement / timedisplacement = velocity timetime = displacement / velocityunitsUnits of speed m/sft/skm/hr(kph)miles/hr (mph)
Units of velocitym/s northft/s southkm/hr westmiles/hr eastHow units are relatedspeed = distance / timedistance - meterstime - secondsspeed = meters / seconds
How units are relateddistance = speed timespeed - meters / secondstime - secondsdistance = meters / seconds seconds = meters
How units are relatedtime = distance / speeddistance = metersspeed = meters / secondstime = meters / (meters / seconds) = secondsPosition and average velocityAnother way to calculate for velocity is to use an objects position with respect to time.
When the object is at point A, its position is 2 meters after 3 seconds and point B is 5 meters after 8 seconds.
Displacement (m)Time (s)ABriserun(3, 2)(8, 5)Position and velocity
Think of slope where we have
Velocity and average acceleration
Velocity (m/s)time (s)ABriserun(3, 2)(8, 5)When the object is at point A, its velocity is 2 m/s after 3 seconds and point B is 5 m/s after 8 seconds.Velocity and acceleration
Think of slope where we have
Practice problems1. A person was running south at a rate of 3 m/s. This person has been running for 3 minutes. How far has this person traveled in the 3 minutes?2. During the first 10 seconds, a car traveled a distance of 800 meters. What is the average speed of the car?3. If the cheetah has been running at a speed of 30 m/s for 8 seconds, how far has the cheetah traveled in this span of time?4. A car slows from a velocity of 40 m/s to 25 m/s in 8 seconds. What is the average acceleration of the car?5. If the average acceleration of an object is 3 m/s2 over a span of time of 2 seconds, what is the change in velocity over the 2 seconds?
top related