KINEMATICS GRAPHS
1)
a. Which sections show the object speeding up? …slowing down?
b. Which sections show positive acceleration? …negative acceleration?
c. When is the object at rest?
d. In which sections is the object moving in the positive direction?
e. What is the object’s displacement at 31 seconds?
f. Find the velocities in sections A, C, and E.
g. Find the average velocity of the object from 16 seconds to 35 seconds.
h. How would you find the object’s velocity at t = 17 seconds?
2)
a. Which sections show the object speeding up? …slowing down?
b. Which sections show positive acceleration? …negative acceleration?
c. At what time does the object stop for just an instant? Is it accelerating at that point? (yes or no)
d. In which sections is the object traveling in the negative direction?
e. What is the object’s total displacement?
f. Find the velocity of the object in sections E and G.
g. How would you find the object’s velocity at t = 1.6 hr?
h. What is the average velocity between 2.4 hr and 9.0 hr?
3)
a. Which sections show the object speeding up? …slowing down?
b. Which sections show negative acceleration? …positive acceleration?
c. During what time interval is the object traveling back toward its starting point?
d. Find the average velocity of the object for the entire time interval.
e. Find the velocity of the object in sections C, E, and I.
4)
a. Which sections show the object speeding up? …slowing down?
b. In which sections does the object have a positive acceleration? …negative acceleration?
c. In which sections is the object traveling in the positive direction?
d. Find the velocity in sections A, C, and G.
e. Find the average velocity from 10. seconds to 35 seconds.
5)
a. Describe the motion of the object through the entire time interval.
b. What is the velocity of the object from 8.0 s to 11 s?
c. Find the object’s acceleration from 2.0 s and 3.0 s.
d. Find the average acceleration of the object for the 14-second interval.
e. Find the total displacement of the object through the 14-second interval.
6)
A ball rolls along the floor, up a sloped board, and then back down the board and across the floor again. This graph represents that motion.
a. At what time is the ball at its highest point?
b. How far up the board did the ball go?
c. What was the acceleration of the ball when it was rolling up the board?
d. What was the acceleration of the ball when it was rolling down the board?
e. What was the acceleration of the ball at the instant it was motionless at the top of the board?
a. Describe the motion of the object in each section.
b. Which sections show positive acceleration?
c. When is the object moving back toward its starting point?
d. When is the object at rest? e. What is the acceleration in section A?
f. Find the average acceleration from 2.0 s to 11 s.
g. Find the total displacement of the object.
8)
a. Find the acceleration of the object in section C.
b. Find the average acceleration through the first 9.0 s
c. Find the object’s displacement for the 13-second trip.
ANSWERS:
1) a. speeding up à 2nd part of B, F slowing down à 1st part of B, D b. + Þ D, F - Þ B c. section E and » 8.5 s d. A, 1st part of B, F, G e. –4.0 cm
f. A = +0.80 cm/s C = -2.3 cm/s E = 0 cm/s g. +0.95 cm/s
h. find slope of line tangent to curve at t= 17 s
2) a. speeding up à D, 2nd part of F slowing down à B, 1st part of F, H b. + Þ B, F - Þ D, H c. » 5.2 hr d. A, B, D, E, 1st part of F e. –5.0 km
f. E = -6.7 km/hr G = +7.5 km/hr g. find slope of line tangent to curve at t= 1.6 hr h. +1.1 km/hr
3) a. speeding up à 2nd part of D, H slowing down à B, 1st part of D, F b. - Þ B, D + Þ F, H c. 2nd part of D, E, F d. +3.2 m/s e. C = +1.0 m/s E = -2.5 m/s I = +12 m/s
4) a. speeding up à B, F slowing down à D, H b. + Þ D, F - Þ B, H
c. F, G, H d. A = 0 m/s C = -6.0 m/s G = +3.0 m/s e. -0.80 m/s
5) b. –40. m/s c. –80. m/s² d. –5.7 m/s² e. 0 m
6) a. at 4.5 sec b. 1.2 m c. –0.27 m/s² d. –0.27 m/s² e. –0.27 m/s²
7) b. A, E c. 2nd part of C, D, E d. at 0 s, 7.0 s, and 14 s e. +2.0 m/s²
f. –0.78 m/s² g. +5.8 m
8) a. –11 m/s² b. +2.8 m/s² c. +320 m