Study Guide Answers Motion In One Dimension Displacement and Velocity, p. 7 1. Yes, from t1 to t4 and from t6 to t7. 5. Yes, from 0 to t1 and from t5 to t6. 2. Yes, from t4 to t5. 6. Yes, from t1 to t2 , from t2 to t4 , from t4 to t5, and from t6 to t7. 3. greater than 7. −5.0 m (or 5.0 m to the west of where it started) 4. greater than Acceleration, p. 8 −v 3. a = i ∆t 1. vf = 0. The car is stopped. 2∆x 2. vi = ∆t 1 5. vi = −a∆t ∆x = 2 vi ∆t −vi2 4. a = 2∆x Falling Objects, p. 9 1. a. −g d. height = g∆t 2/8 b. initial speed = g(∆t/2) c. 1.2 s 2 2. a. −9.81 m/s c. elapsed time = ∆t/2 b. 12 m/s Mixed Review, pp. 11–12 2. a. vf = a(∆t) b. total distance = d1 + d2 + d3 1 b. vf = vi + a(∆t); ∆x = 2(vi + vf )∆t or ∆x = vi (∆t) + 1 a(∆t)2 2 c. total time = t1 + t2 + t3 3. Time interval Type of motion v (m/s) a(m/s2) A B C D E speeding up speeding up constant velocity slowing down slowing down + + + + + + + 0 − − 4. a. III–2 b. 1 s 2 Time (s) Position (m) v (m/s) a(m/s ) 1 2 3 4 4.9 0 −14.7 −39.2 0 −9.8 −19.6 −29.4 −9.81 −9.81 −9.81 −9.81 Holt Physics Solution Manual c. 2 s Copyright © by Holt, Rinehart and Winston. All rights reserved. III 1. a. t1 = d1/v1; t2 = d2 /v2 ; t3 = d3 /v3