displacement
a person walks 10m to the right and then 10m back to the left. what is their total distance traveled, and displacement
20m total and 0m displacment
is acceleration a vector or a scalar and why
Vector. The velocity has a direction, so something you calculate from the velocity also has a direction
a person jogs a full lap on a 1km long oval track in 500 seconds. what is the average speed of the trip? average velocity?
2m/s, 0m/s. dont forget to convert to standard units of velocity which is m/s
what is acceleration of an object thrown upwards with no air resistance
-g. acceleration is always constant in free fall
What quantity is represented by the slope of a position-versus-time graph?
velocity
If I travel 3 miles north and then 4 miles south. What is the displacement? What is the magnitude of the displacement? What is the total distance traveled?
1m south. 1m. 7m
the temperature is predicted to be −5ºC. Is this temperature a vector or a scalar quantity?
Scalar. In this case the negative sign does not indicate direction, because temperature doesn’t have a direction. The negative sign indicates a lower value.
If you divide the total distance traveled on a car trip (as determined by the odometer) by the time for the trip, are you calculating the average speed or the magnitude of the average velocity?
average speed. speed uses total distance
if a subway train is moving to the left and slows down what is the acceleration?
right and positive
On a velocity vs time graph, what does a horizontal line mean
constant velocity, acceleration is 0
a runner starts at x=3m, runs to x=19m, then returns to x=8m. what are the runner's total distance traveled and final displacement
27m distance and 5m displacement
A student writes, “A bird that is diving for prey has a speed of −10𝑚/𝑠.” What is wrong with the student’s statement? What has the student actually described?
Speed is always positive and has no direction. The student has described velocity, because the negative sign indicates direction.
what is the difference in average speed and the magnitude of average velocity
speed uses distance, it includes the total path the object travelled, while velocity uses displacement, so it only uses initial and final positions.
a car's velocity changes from 30m/s to 10m/s in 5seconds. what is the acceleration
-4m/s^2
a position vs time graph gets progressively steeper in the negative direction. what is happening to the objects velocity
The objects velocity is increasing but it is moving backwards
When does distance traveled equal magnitude of displacement?
walking in a straight line
Classify each as scalar or vector: distance, displacement, speed, velocity
scalar
vector
scalar
vector
give an example the illustrates the difference in avg speed and the magnitude of avg velocity. give an example where it would be the same.
if you travel in a circle, your speed is your total distance traveled over 0 but your velocity is 0 since displacement is 0. if you travel in a straight line in the positive direction, it will be the same
Is it possible for speed to be constant while acceleration is not zero? Give an example of such a situation.
Yes. If you are changing direction but not magnitude, you would have a constant speed but not a constant acceleration
Imagine a position-vs-time graph that:
Question: Describe the object's motion.
it moves in the positive direction, stops, moves in the negative direction
what is the only case in which magnitude of displacement and displacement are exactly the same?
walking in the positive direction
you define left as positive. an object has a velocity of -3m/s. what does the negative sign tell you
the object is moving to the right
what equation can be used to calculate average velocity
avg velocity= delta x/ delta t
if your velocity is constant, your acceleration is
zero
you are given an acceleration vs time graph showing constant negative acceleration. what should the velocity time graph look like? position vs time?
a straight line with a negative slope. a curved line going downwards.