Proportional Reasoning
A dog is running away from the house at a constant velocity. How much farther will the dog travel if he runs at the same constant velocity for triple the time?
3x as far
Fill in a T-chart (x and y) for everything you know about a horizontal launch.
ax = 0 m/s
ay = -9.8 m/s
vy = 0 m/s
An elevator is moving upward with a speed of 11 m/s. Three seconds later, the elevator is still moving upward, but its speed has been reduced to 5.0 m/s. What is the average acceleration of the elevator during the 3.0 s interval?
-2.0 m/s2
On a position vs. time graph how do you show that you are moving forwards or backwards?
With positive or negative slope
Describe the difference between a vector and a scalar quantity. Provide an example of each.
Vector - a quantity that has magnitude and direction (example: velocity, displacement)
Scalar - a quantity with magnitude only (example: speed, distance)
A rock is thrown with a velocity of +10 m/s, reaching a maximum height of h. What will the maximum height be if the rock was then thrown with an initial velocity of +20 m/s.
4 x the original height
The launcher is still set to launch perfectly horizontally at a height of 3.2 m above the ground. Mrs. Wrona fires the launchers and measures the range of the launch to be 2.7 m from the base of the launcher. Use this information to find the initial velocity of the ball when the launcher fires it from the medium setting.
Starting from rest, a car confined to move along a straight line is accelerated at a rate of 17 m/s2. What is the speed after it has traveled 5 m?
v = 13.04 m/s
Draw the velocity vs. time graph for an object that starts with an initial velocity and rolls up the ramp before then rolling back down the ramp.
V vs. T graph should include:
- Axes with units
-Constant negative slope, crossing the t-axis
A ball accelerates at a rate of 10 m/s2. Using only words, explain what this means.
The ball is changing velocity (speeding up or slowing down) by 10 m/s every second
Starting from rest, Ms. One starts sprinting down the 1600 hallway at SHS, accelerating at a rate of "a". Determine how Ms. One's distance would change if she sprints at the same hallway at the same rate of acceleration, but for HALF of the time.
1/4 of the original distance
A long jumper leaves the ground at an angle of 32° to the horizontal and at a speed of 16.3 m/s. How long does it take her to reach her maximum vertical height?
t = 0.88 seconds
A horse that accelerates for 4 seconds at a rate of 2.1 m/s every second to reach a velocity of 10 m/s. What was the initial velocity of the horse?
v = 1.6 m/s
Draw the TWO velocity vs. time graphs that show positive acceleration.
TWO v vs t with positive slopes:
Positive line above t-axis going away from 0
Positive line below t-axis going towards 0
You drop a golf ball and a bowling ball from the top of a ladder. Which one will hit the ground first and why?
They will both hit the ground at the same time. Both objects are dropped from rest and accelerate towards the ground at -9.8 m/s2. Mass does not matter.
Chris can throw a baseball 24.2 m high. How many times faster would he need to throw it if they wanted to triple the height of the ball?
1.73 x the original
At what point is an object moving the fastest during projectile motion in the symmetrical launch? How do you know?
At the beginning and at the end because that is when vy is the largest.
A runner has an initial velocity of 4.1 m/s. She runs for 10 seconds before coming to a halt. How far has she traveled?
x = 20.5 m
Linearize the following graph and write a physics equation.
Length vs. Velocity (square root)
Slope: 4
Y-intercept: 2
L2 = (4 ms) v + (2 m2)
You can find displacement using a velocity v. time graph by finding the area on the curve. How does that work out? (Hint: explain using units)
If you take the area of any object, you are multiplying base x height. The base units are seconds and the height units are m/s. If you multiple the two units by one another = seconds x m/s = meters.
What is the hang time for MJ, whose vertical is 1.22 m.
time = 0.997 seconds (esentially, 1 whole second!)
What is the VALUE of the slope of a graph with an object in free fall with the axes velocity2 (v2) and displacement (x)?
2a = 2(-9.8) = -19.6 m/s2
For a projectile problem where the starting and ending height are the same, what launch angle gives the largest range and why?
45° will give you the largest range because you need to maximize the equation x = vt + x.