12.13. A toy car travels clockwise in a semi-circular path of radius r = 3.0m at...

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12.13. A toy car travels clockwise in a semi-circular path of radius r = 3.0m at a constant speed of |||| 4.8 m/s. -3 = A t = Os 82 B a. Since the car always moves with constant speed, then what is the car's instantaneous speed at any particular time, for instance at 1s? b. Find the instantaneous velocity vector at points A, B, C. Write your answer in terms of . ANS: At C: -4.7 - 0.67 13.12. a. What is the equation that relates the instantaneous velocity at time t = t to the average velocity from t = t to t = t2. Explain what the symbol means in your answere. b. In the lecture notes you see the following picture. What is this picture trying to show us? Give your answer as a short sentence. y t1 A Vavg Vavg D t t Vavg 47 B t = t C t > t x 8 31 Dashboard Calendar To Do Notifications Inbox 2:29 AM Tue Mar 12 Back 2ag HCHW Ch 3 (18).pdf C. What are the 3 steps to drawing an instantaneous velocity vector at a point on the path? d. What is the rule for drawing the average velocity from the times t = t to t = t? HELP: See page 14 of notes. 14.12.The path of a moving object is given by the two equations x = t 1 2 - y: = -t + 10t 18 = = 3s and t = 5s. Give your answer as components where x, y are in meters and t is in seconds. a. Compute the postion vector at t x, y b. Find the average velocity from t = 3s to t Vavg,x, Vavg,y = 5s. Give your answer as components Find the instantaneous velocity at t = 3s by computing the average velocity from = 3s and t = 3s+ 0.1s as an approximation. Give your answer as components C. t Vx, Vy d. Use what you said in problem = #13 to draw the four vectors below on the graph 3s i. position vector at t ii. position vector at t = 5s iii. average velocity from t iv. instantaneous velocity at t = 3s to t = 5s = 3s y [m] 5 O 5 10 x [m] 100% 15.C. IDEA: horizontal and vertical vectors are different and simpler than most general vectors that look diagonal. A. The velocity vector seen below has |||| = 10 m/s Is it vertical or hoirizontal? Find its components Vx and Vy True or false: We can write symbolically v = ||||| 9 31 Dashboard Calendar 000 To Do Notifications Inbox 2:29 AM Tue Mar 12 Back 100% 2ag HCHW Ch 3 (18).pdf B. The acceleration vector seen below has ||a|| = 4 m/s True or false: We can write symbolically ax = -||a|| C. Suppose A reprsents any horizontal vector. A can be position, displacement, velocity or acceleration. Is it vertical or hoirizontal? Find its components ax and ay True or fasle: Ay = 0 Explain with a short sentence under what circumstances Ax D. The velocity vector seen below has |||| = 5 m/s = ||A|| versus Ax = |||| Is it vertical or hoirizontal? Find its components vx and Vy True or false: We can write symbolically v = |||| E. The acceleration vector seen below has ||a|| = 3 m/s Is it vertical or hoirizontal? Find its components ax and ay True or false: We can write symbolically ay F. Suppose reprsents any vertical vecto. acceleration. True or fasle: Ax = 0 = -||a|| A can be position, displacement, velocity or G. Explain with a short sentence under what circumstances A = |||| versus A = ||||. H. Seen below is a generic vector A. Can we say it is a horizontal or vertical vectoir? Yes. or no? Find ||A|| Explain using a short sentence why we can NOT say that Ax ||A|| and A = ||A||. In other = words, write a symbolic formula that correctly relates the three quantities Ax, Ay, and ||A|| HELP: Pythagorean Theorem. 6 10 = 12.13. A toy car travels clockwise in a semi-circular path of radius r = 3.0m at a constant speed of |||| 4.8 m/s. -3 = A t = Os 82 B a. Since the car always moves with constant speed, then what is the car's instantaneous speed at any particular time, for instance at 1s? b. Find the instantaneous velocity vector at points A, B, C. Write your answer in terms of . ANS: At C: -4.7 - 0.67 13.12. a. What is the equation that relates the instantaneous velocity at time t = t to the average velocity from t = t to t = t2. Explain what the symbol means in your answere. b. In the lecture notes you see the following picture. What is this picture trying to show us? Give your answer as a short sentence. y t1 A Vavg Vavg D t t Vavg 47 B t = t C t > t x 8 31 Dashboard Calendar To Do Notifications Inbox 2:29 AM Tue Mar 12 Back 2ag HCHW Ch 3 (18).pdf C. What are the 3 steps to drawing an instantaneous velocity vector at a point on the path? d. What is the rule for drawing the average velocity from the times t = t to t = t? HELP: See page 14 of notes. 14.12.The path of a moving object is given by the two equations x = t 1 2 - y: = -t + 10t 18 = = 3s and t = 5s. Give your answer as components where x, y are in meters and t is in seconds. a. Compute the postion vector at t x, y b. Find the average velocity from t = 3s to t Vavg,x, Vavg,y = 5s. Give your answer as components Find the instantaneous velocity at t = 3s by computing the average velocity from = 3s and t = 3s+ 0.1s as an approximation. Give your answer as components C. t Vx, Vy d. Use what you said in problem = #13 to draw the four vectors below on the graph 3s i. position vector at t ii. position vector at t = 5s iii. average velocity from t iv. instantaneous velocity at t = 3s to t = 5s = 3s y [m] 5 O 5 10 x [m] 100% 15.C. IDEA: horizontal and vertical vectors are different and simpler than most general vectors that look diagonal. A. The velocity vector seen below has |||| = 10 m/s Is it vertical or hoirizontal? Find its components Vx and Vy True or false: We can write symbolically v = ||||| 9 31 Dashboard Calendar 000 To Do Notifications Inbox 2:29 AM Tue Mar 12 Back 100% 2ag HCHW Ch 3 (18).pdf B. The acceleration vector seen below has ||a|| = 4 m/s True or false: We can write symbolically ax = -||a|| C. Suppose A reprsents any horizontal vector. A can be position, displacement, velocity or acceleration. Is it vertical or hoirizontal? Find its components ax and ay True or fasle: Ay = 0 Explain with a short sentence under what circumstances Ax D. The velocity vector seen below has |||| = 5 m/s = ||A|| versus Ax = |||| Is it vertical or hoirizontal? Find its components vx and Vy True or false: We can write symbolically v = |||| E. The acceleration vector seen below has ||a|| = 3 m/s Is it vertical or hoirizontal? Find its components ax and ay True or false: We can write symbolically ay F. Suppose reprsents any vertical vecto. acceleration. True or fasle: Ax = 0 = -||a|| A can be position, displacement, velocity or G. Explain with a short sentence under what circumstances A = |||| versus A = ||||. H. Seen below is a generic vector A. Can we say it is a horizontal or vertical vectoir? Yes. or no? Find ||A|| Explain using a short sentence why we can NOT say that Ax ||A|| and A = ||A||. In other = words, write a symbolic formula that correctly relates the three quantities Ax, Ay, and ||A|| HELP: Pythagorean Theorem. 6 10 =