Distance & Displacement
An elephant walks 0.5 miles in the positive direction, then 2 miles in the negative direction.
Find the elephant's distance and displacement.
Make sure your answers have the proper unit!
distance = 0.5 + 2
distance = 2.5 miles
Displacement = 0.5 - 2
Displacement = -1.5 miles
A cat ran 55 feet in 4.4 seconds. What is the cat's average speed?
Show your work and include the proper unit in your answer!
s = distance / time
s = 55 / 4.4
s = 12.5 ft/s
Acceleration is change in _______________ over time.
Fill in the blank.
velocity
An object is moving in the positive direction and slowing down. Is its acceleration positive, negative, or 0?
Negatve
What is the numerical value for g on Earth?
Include the proper unit!
-9.8 m/s2
A hiker walks 7 kilometers north, then 4 kilometers south.
Find the hiker's distance and displacement.
Make sure your answers have the proper unit!
Distance = 7 + 4
Distance = 11 km
Displacement = 7 - 4
Displacement = 3 km North
How long will it take to reach Madison, WI by train if it is 150 miles away and the train travels at a speed of 60 mi/hr?
Show your work and include the proper unit in your answer!
t = d / s
t = 150 / 60
t = 2.5 hours
If an object is accelerating, that means it is either ___________, ___________, or ___________.
Fill in all 3 blanks.
It is either speeding up, slowing down, or changing direction.
An object is moving in the negative direction and speeding up. Is its acceleration positive, negative, or 0?
Negative
A balloon and a brick are both dropped from the same height at the same time in a vacuum (where there is no air). Which will hit the ground first and why?
They will hit the ground at the same time because without air resistance, all things fall at the same rate. This is because gravity pulls on all things equally.
An ant walks 8 cm in the positive direction, then 5 cm in the negative direction, then 4 cm in the positive direction, then 6 cm in the negative direction
Find the ant's distance and displacement.
Make sure your answers have the proper unit!
Distance = 8 + 5 + 4 + 6
Distance = 23 km
Displacement = 8 + -5 + 4 + -6
Displacement = 1 cm in the positive direction
A math teacher goes on a road trip. He counts the miles he travels and the time it takes him and uses the equation s=d/t to calculate his speed for the trip as 40.6 mi/hr.
But at one point during the journey, he looked at his speedometer and saw that his speed was 60 mi/hr. How is this possible?Hint: A correct answer will include 2 pieces of vocab from this unit!
40.6 mi/hr is the average speed for the whole trip.
60 mi/hr is the instantaneous speed he was going in that moment.
A cart being pushed changes its velocity from 0.5 m/s to 4.5 m/s over the course of 10 seconds. What is the cart's acceleration?
Show your work and include a proper unit!
a = (vf - vi) / t
a = (4.5 - 0.5) / 10
a = 4/10
a = 0.4 m/s2
An object's velocity is negative and its acceleration is positive. Is it speeding up, slowing down, moving at a constant velocity, or not moving?
It is slowing down
A penny is dropped in a vacuum. What will be its velocity after it has been falling for 4 seconds?
Show your work and include the proper unit in your answer!
v = g * t
v = -9.8 * 4
v = -39.2 m/s
Write a scenario where the distance is 100 m and the displacement is 0 m.
Many possible answers (but it should involve the subject ending up in the same place where they started)
A skateboarder travels 8 km in the negative direction. This takes 18 minutes.
Calculate the skateboarder's average speed AND their average velocity.
Show your work and include the proper unit in your answer!
s = distance/time
s = 8/18
s = 0.4444444 km/min
v = displacement/time
v = -8/18
v = -0.444444 km/min
A car is moving at 50 m/s when the driver hits the breaks. After 4 seconds, the car comes to a complete stop. What is the car's acceleration?
Show your work and include a proper unit!
a = (vf - vi) / t
a = (0 - 50) / 4
a = -50 / 4
a = -12.5 m/s2
An object's velocity is 0 and its acceleration is 0. Is it speeding up, slowing down, moving at a constant velocity, or not moving?
It is not moving
Describe in words what g represents.
It is the gravitational acceleration / acceleration due to gravity of all things when there is no air resistance present.
Write a scenario where the distance is 10 m and the displacement is -2 m.
Something moved 6 m in the positive direction and 4 m in the negative direction.
A runner goes around a 500 meter track 3 times. This takes 15 minutes.
Calculate the runner's average speed AND their average velocity.
Show your work and include the proper unit in your answer!
distance = 500 * 3
distance - 1500 m
s = distance/time
s = 1500/15
s = 100 m/min
v = displacement/time
v = 0/15
v = 0 m/min
A ball rolling down a hill speeds up, going from -1 m/s to -23 m/s over the course of 5 seconds. What is the ball's acceleration?
Show your work and include a proper unit!
a = (vf - vi) / t
a = (-23 - -1) / 5
a = -22 / 5
a = -4.4 m/s2
An object's velocity is positive and its acceleration is 0. Is it speeding up, slowing down, moving at a constant velocity, or not moving?
It is moving at a constant velocity.
Two identical balls are dropped from the same height, at the same time. But one is in a vacuum (where there is no air) while the other one is in a normal environment (where there is air). Which one will hit the ground first, and why?
The one in the vacuum will hit the ground first because it doesn't have air resistance slowing it down.