Please have your tennis ball lab or a yellow NTI form on your desk #. Also the mixed review (5 or 6 problems) Bell Work: Free Fall Again. Rock A is dropped from a bridge as rock B is thrown up. ( A / B / Both ) will have the greatest speed when they hit the water?
Rock A is dropped from a bridge as rock B is thrown up.
( A / B / Both ) will have the greatest speed when they hit the water?
( A / B / Both ) will have the greatest acceleration?
( A / B / Both ) will hit the water first?
( A / B / Both ) will travel a greater distance?
( A / B / Both ) will have a greater displacement?
2. What your desk #. is a scalar quantity?
A quantity that is specified by a magnitude (numerical) value only.
Example: 40 m/s
3. What is a vector quantity?
A quantity that is specified by a magnitude and a direction.
Example: 40 m/s North
4. your desk #. A Lanier High School student begins at the starting line facing west (180o) and runs around the track 20 times before returning to the starting line. (1 lap = 400m)
a. What is his displacement?
0 meters, they ended where they started
a. What is David’s displacement?
800 N + (-200 S) + 300 N= 900 miles, North
6. An your desk #. object is accelerating when its speed or direction changes.
7. An object is speeding up when its velocity and acceleration are in ( the same / opposite ) direction(s). An object is slowing down when its velocity and acceleration are in ( the same / opposite ) direction(s).
8. A wheel is spinning at 3.7 m/s. Its (speed/ direction ) does not change.
9. The your desk #. average velocity of an object is equal to the instantaneous velocity when the object has a ( constant / changing ) velocity.
10. Suppose that an object is moving with a constant velocity. a = _0_m/s2
11. The speed of an object at rest is 0m/s.
12. A your desk #. runner sees the finish line and accelerates at a rate of 1.5 m/s2 for the last 7.0 seconds to win the race. If he was initially running at a speed of 3.4 m/s, how far did he travel?
Vo= 3.4 m/s x= 3.4 (7) + .5 (1.5) (7)2
Vf = x = 23.8 + .5 (1.5) (49)
t = 7 s x = 23.8 + 36.75
a = 1.5 m/s2 x = 60.55 m
X = ?
13. A your desk #. car is traveling 55 miles during the first hour, 55 miles in the second hour and 55 miles in the third hour. Its acceleration is ____.
0 m/h2, maintained 55 mi/h, therefore, no acceleration occurred.
14. You traveled 340 km in 5.5 hours. What is your average speed?
GIVEN: v = x/t
v = ? v = 340
d = 340 km 5.5
t = 5.5 hours v = 61.8 km/h
15. A your desk #. car's velocity increases from 7.0 m/s to 45 m/s over a 8.0 s time interval. What is its acceleration?
Vo= 7.0 m/s
Vf= 45 m/s -7 -7
t = 8.0 s
a = ? a = 4.75 m/s2
16. You are driving down the highway when you want to pass someone traveling at 30 m/s. You decide to change lanes and accelerate at 3.3 m/s2 for the next 3.0 s. What is your final velocity?
Vo = 30 m/s Vf = 30 + (3.3)(3.0)
Vf = ? Vf = 30 + 9.9
t = 3.0 s
a = 3.3 m/s2 Vf = 39.9 m/s
17. On your desk #. a position (distance) vs. time graph you can use the slope of your line to determine the ball's average velocity.
18. The slope of a tangentline at a given time value on a position versus time graph gives instantaneous velocity.
a. What is the average velocity of the object between times t=0 and t=5? (Find the Slope)
25 – 0 m = 25 m = 5 m/s
5-0 s 5 s
b. What range of time shows the car at rest?
5s – 10 s
c. What is the instantaneous velocity of the object at 9 seconds?
20. your desk #. Suppose a ball is thrown straight up, reaches a maximum height, and falls to its initial height. While going up, the velocity vector points ( up / down ) and the acceleration vector points ( up / down ). While going down, the velocity vector points ( up / down ) and the acceleration vector points ( up / down ).
21. A ball is thrown straight up. At the top of its path its instantaneous speed is 0 m/s
22. A ball is thrown straight up. At the top of its path, its acceleration is -9.8 m/s2.
23. If you drop a feather and coin at the same time in a vacuum tube, which one experiences the greater acceleration?
Neither, they will both experience the same amount of acceleration.
Vo = 20 m/s (0) 2 = (20) 2 + 2 (-9.8)(x)
Vf = 0 m/s 0 = 400 - (19.6) (x)
0-400 = 400-400-19.6x
t = -400 = - 19.6 (x)
a = -9.8 m/s2 -19.6 - 19.6
x = ? x = 20.4 m
vo= 0 x = 0 + ½ (-9.8) (4.3)2
vf= x = .5 (-9.8) (18.49)
t = 4.3 s x = -90.6 m
a = -9.8 m/s2
x = ?
26. A your desk #. ball is dropped from a height of 1.0 m. A digital camera takes a picture every 1/30th of a second. Which group of circles to the right shows the data taken by the camera?
Z. Dots are moving further
and further apart. When
the time doubles, the
27. Use your desk #. the graphs to answer questions a-b.
a. Which graph shows a car speeding up?
b. Which graph shows a car slowing down?
28a. How many hours are in 4567 seconds? your desk #.
28b. How many miles are in 2567000 meters?
( 1 mile = 1.609 km)
28c. your desk #. How many lbs are in 234 kg?
(1 kg = 2.2 lbs)
28d. Jennifer Anniston’s new engagement ring is said to be 8 carats, how many mg is that?
(1 carat = 200mg)