CH 1-2 Review
Convert 65 miles/hour to meters/second
Given: 1 miles = 1609 meters
29 m/s
What is the name of the path a projectile takes and what is its general shape?
trajectory, parabolic
Joe walks 12.0 m north, 12.0 m west, and then 10.0 m south. What is the magnitude of his displacement?
12.3 m
Describe the vectors of acceleration and horizontal motion of any projectile (ignoring air resistance)
acceleration - always g (-9.81 m/s2)
horizontal velocity - always whatever it was initially
Joe walks across the aisle 3 m over the course of 3 seconds on a train to show his friend something on his phone. If the train is going 27 m/s what is the magnitude of Joe's velocity from the frame of reference of the train?
1 m/s
2 students measure the same object three times using different tools.
Student A measures 0.3g, 0.4g, 0.3g.
Student B measures 0.34g, 0.36g, 0.34g.
Which student had greater precision? What would we need to decide who was more accurate?
B was more precise, we need to know the 'true' value before we can determine accuracy
A certain vector is at an angle between 0 and 90 degrees. What name is given for the two vectors who are horizonal and vertical and would add to that vector?
component vectors
A shopper pushes a cart 40.0 m south down one aisle and then turns 90.0 degrees left and moves 15.0 m. Then turns 90 degrees left again and walks 20.0 m. What is the shoppers overall displacement?
25.0 m at 36.9 degrees E of S or 53.1 degrees S of E
Describe the vector of vertical velocity of a projectile launched upward at an angle over the course of its launch
positive and getting smaller until it reaches zero, then gets more negative over time
Joe walks across the aisle 3.00 m over the course of 3.00 seconds on a train to show his friend something on his phone. If the train is going 27.0 m/s what is the magnitude of Joe's velocity from the frame of reference of the ground?
27.2 m/s
Any straight line on a position-time graph would tell you the object in question's velocity is...
constant
When vectors are added, the answer is called the...
resultant vector
sin/cos/tan to find a side of a triangle
inverse functions to determine angle
Imagine a cannonball dropped and another cannonball launched horizontally off a cliff. Describe when the hit the ground and their final velocity (before impact)
same landing time, launched one faster final velocity
A boat aims 27 degrees upstream and launches at 12.0 m/s relative to the water which is moving 3 m/s. What is the velocity of the boat relative to the shore?
11.0 m/s at 12.6 degrees upstream
A track is about 400m around. If a runner does 4 laps and then runs past the finish line by 20 meters before coming to a stop, determine their distance and displacement for the race.
1620 m - distance
+20 m - displacement
What is another way to say -30m/s west?
30 m/s east
Describe how to find the time of a fall if you know the height of the fall of a horizontally launched object.
t = square root (height / (0.5 x g))
If velocity is negative and acceleration is positive, what happens to the object's speed?
What are 2 challenges of using graphical methods to add vectors rather than mathematical? (in other words, why is using trig/math a benefit over relying on graphing methods)
Ensuring a quality scale, measuring angles correctly, speed, etc.
A spy in a speed boat is being chased down a river by another boat, they catch up to each other just as they reach a 5 m waterfall. If boat A's launch speed is 15m/s and boat B's launch speed is 26 m/s, how far apart will they be after they land in the water below?
11 m