Speed & Intervals
A runner travels 60 meters in 12 seconds. What is the runner’s average speed?
60 m/12 s = 5 m/s
What does a horizontal line on a distance-time graph represent?
The object is stopped because its distance is not changing.
What upward contact force prevents a book from falling through a table?
The normal force.
Which measurement describes the total length of the path traveled?
Distance
In a sealed container, 22 grams of one reactant combines with 8 grams of another reactant. What is the total mass of the products?
22 + 8= 30 g
A cyclist travels at an average speed of 4 m/s for 15 seconds. How far does the cyclist travel?
D=SxT
4 x 15 = 60 m
Two lines rise on a distance-time graph. Line A is steeper than Line B. Which object is moving faster and why?
The object represented by Line A because a steeper slope indicates a greater speed.
A passenger continues moving forward when a vehicle suddenly stops. Which Newton’s law explains this?
Newton’s First Law, also called the law of inertia
A student walks 7 meters east and then 3 meters west. Determine the total distance and displacement.
Distance: 7+3= 10 m
Displacement: 7-3 = 4 m east
A sample is shiny, malleable, and conducts electricity well. Is it most likely a metal or nonmetal?
METAL
At 2 seconds, an object is 6 meters from the start. At 8 seconds, it is 30 meters from the start. What was its average speed during this interval?
D = 30-6 | T = 8-2
24/6 = 4 m/s
A graph showing an object’s distance from its starting point slopes downward. What is happening?
The object is moving back toward its starting point
A balloon moves forward while air rushes backward out of its opening. Which Newton’s law does this demonstrate and explain the force pair?
Newton’s Third Law: the balloon pushes air backward (action), and the air pushes the balloon forward (reaction).
A runner travels 100 meters around a track and finishes at the exact starting point. What is the runner’s distance and displacement?
Distance: 100 meters
Displacement: 0 meters
3CO2 + 2O2 > products
How many oxygen atoms are on the reactants?
10 Oxygen atoms
A robot travels 50 meters in 10 seconds and then 30 meters in 5 seconds. What was its average speed for the entire trip?
D = 50 + 30
T = 10 + 5
80/15 = 5.33 m/s
Time: 0 s, 2 s, 5 s, 7 s
Distance from Start: 0 m, 8 m, 8 m, 2 m
Describe the object’s motion during all three intervals.
0–2 seconds: moving away from the start
2–5 seconds: stopped
5–7 seconds: moving back toward the star
A 14 kg cart is pushed right with 60 N. Friction pushes left with 18 N. Calculate the cart’s acceleration.
Net Force = 60 N -18 N = 42 N
A = 42 N/14 kg = 3 m/s2
A robot travels 40 meters east, 15 meters west, and then 12 meters east. Determine its total distance and displacement.
Distance = 40+15+12 = 67 m
Displacement 40-15+12 = 37 m east
4Al + 3O2 > 2Al2O3
How many oxygen atoms are on each side, and is oxygen conserved?
Reactants = 6
Products = 6
Yes, oxygen is conserved because both sides contain 6 oxygen atoms.
A cyclist travels 36 meters in 12 seconds. If the cyclist maintains the same average speed, how far will the cyclist travel in 25 seconds?
36 m/12 s =3 m/s
3 m/s x 25 = 75 m
Time: 0 s, 2 s, 5 s, 7 s
Distance from Start: 0 m, 8 m, 8 m, 2 m
What total distance did the object travel, and what was its average speed for the entire seven seconds?
D = 8 + 6= 14 m
Average Speed = 14 m / 7s = 2 m/s
Evelyn pushes a 10 kg box right with 35 N while friction acts left with 15 N. Evelyn then releases the box. Describe the forces and motion both before and after release.
F = 35 N - 15 N = 20 N right
A = 20 N/10 kg = 2 m/s2
After release, the applied force ends. Friction continues acting left, causing the box to slow down and eventually stop.A hiker walks 18 meters north, 50 meters south, and then 12 meters north. Determine the hiker’s total distance and displacement.
Distance = 18+50+12= 80 m
Displacement = 18-50+12 = -20
20 m south
2Fe2(SO4)3 + 6KOH > products
How many total oxygen atoms are on the reactant side?
24 + 6 = 30 oxygen atoms