Errata for Motion TG

Activity 4, p. 22, question P8, part (a) answer

  • Add graph D to the list of answers, i.e., "Graphs C, D, and E represent objects that are speeding up."

Activity 8, p. 39, "Link to Reader"

  • Change the ending page of the reading assignment to R9, i.e., "Students may read pages R8-9 (the beginning of section 1.4, Velocity) after finishing Activity 9."

Activity 9, p. 45, "Link to Reader"

  • Change the ending page of the reading assignment to R9, i.e., "Students may read pages R8-9 (the beginning of section 1.4, Velocity) after finishing this activity."

Activity 9, p. 46, "Probing for Student Understanding", question P3

  • In parts (a) and (c), change the units to cm/s, i.e., "P3. (a) Which object (in part A) reaches a velocity of 1cm/s first? (b) When does this occur? (c) Which object reaches a speed of 1cm/s first? (d) When does this occur?"

Activity 12, p. 65, question A4 answer, bullet 1

  • Change wording to "Students might plot speed vs. time instead of velocity vs. time (as shown below on the left). In addition, some students might not realize that the speed goes to zero between strobes 4 and 5 (as shown below on the right)."

Activity 12, p. 68, question B4 answer

  • Change answer to "after t = 0.45s".
  • Add third bullet, "• By exaggerating the curvature of the graph between #4 and #5, you can see that the marble is at the 1m mark just after the midpoint in time."

Activity 13, p. 76, question P1 answer

  • In part (a), at t = 1½s, object X is at x = 7½cm.

Activity 14, p. 79

  • question A2 answer, bullet 1, "Object J has the largest displacement..."
  • question A4 answer, bullet 1, "Students might pick only object J, because object I..."
  • question A4 answer, bullet 2, "Students might pick only object I..."
  • question A6 answer, "... which would correspond to J"
  • question A6 answer, bullet 1, "Students might pick object I because the curves for objects E and I look the same."

Activity 15, p. 86, question P1 answer

  • The answers to parts (a) and (b) are reversed.

Activity 16, p. 91, question C3 answer

  • Modify paragraph 2: "Yes, this answer agrees..."
  • Fix bullet 1: "Students might have gotten question B2 wrong."

Activity 17, p. 96, question A5 answer

  • Add to the end of paragraph 1, "At 20km/h, the plane travels about 5½km before losing contact with the car."
  • Add to the end of bullet 1, "i.e., after the plane has traveled 20km".

Activity 19, p. 107, question P4 answer

  • The speed is only 1 grid/s, i.e., the answer should read, "... the average velocity is +1 grid/s —or— 1 grid/s, to the right between 2s and 6s."

Activity 23, p. 131, question P8 answer

  • Add bullet, "• See table of values for P1 above."

Activity 24, p. 137, question B1 answer, bullet 4

  • Change A2-A4 to B2-B4, i.e., "Students do not need to make precise calculations to answer questions B2-B4."

Activity 25, p. 145, question A2 answer

  • In part (i), the Total Area (i.e., column 4) should be 292.5 m.

Activity 27, p. 163

  • question R2 answer is really only the first half of the answer to R2.

  • question R3 answer is really the second half of the answer to R2.

  • question R4 answer is really the answer to R3.

  • question R5 answer is really the answer to R4.

Many thanks to Lonnie Grimes of Oakmont High School in Roseville, CA, who found almost all of these mistakes.