Displacement and velocity, with a frame of reference
Grade 11 Science Worksheet - Challenge Me
Circle the best answer, or write your answer on the line.
East is positive. At t = 0, Ari's cart A is at x = 0 moving 4 m/s; cart B is at x = 60 m moving -2 m/s. When do they meet?
East is positive. At t = 0, Bo's cart A is at x = 0 moving 7 m/s; cart B is at x = 54 m moving -2 m/s. When do they meet?
East is positive. At t = 0, Esme's cart A is at x = 0 moving 8 m/s; cart B is at x = 75 m moving 3 m/s. When do they meet?
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Cart position each second (example data)
time (s) position (m) 0 0 1 6 2 8 3 6 4 0 5 -10 In the position table, when does the cart reverse direction, Jun?
- At 4 s, when x is back at 0 m, the origin
- At 5 s, the last reading in the table
- At 0 s, when the cart starts moving
- At 2 s, where x stops rising and starts falling
A plane has an airspeed of 250 m/s. The wind blows 50 m/s toward the east. To fly due north, what heading and ground speed does Luz need?
- Head 78.5° west of north; ground speed about 245 m/s
- Head 11.5° west of north; ground speed 250 m/s
- Head 11.5° west of north; ground speed about 245 m/s
- Head due north; ground speed about 245 m/s, drifting east
Milo says: "I drove 120 km in 2.0 h, so my average velocity was 60 km/h." The trip ended 30 km from the start. Find the flaw.
- 60 km/h is the average speed; the average velocity is 15 km/h
- The average velocity is 60 km/h, but the speed is 15 km/h
- No flaw: speed and velocity mean the same thing here
- The average velocity is 30 km/h, the distance from the start
Noah says two cars at 60 km/h have equal velocities. One drives east, the other north. Judge the claim and find their relative velocity.
- False: only the speeds match; relative velocity is 60 km/h
- False: only the speeds match; relative velocity is about 85 km/h
- True: both are 60 km/h, so the relative velocity is 0
- False: only the speeds match; relative velocity is 120 km/h
Rain falls straight down at 6.0 m/s. Ren cycles east at 8.0 m/s. What is the rain's speed relative to the cyclist, and its angle from the vertical?
- 14 m/s, 53° from the vertical, coming from ahead
- 10 m/s, 53° from the vertical, coming from behind
- 10 m/s, 37° from the vertical, coming from ahead
- 10 m/s, 53° from the vertical, coming from ahead
Tala rides a moving escalator up in 20 s, or walks up the stopped escalator in 30 s. How long to walk up the moving one?
- 10 s, the difference of 20 and 30
- 12 s: the two rates add up
- 50 s, the sum of 20 and 30
- 25 s, the average of 20 and 30
Zee rides a train at a steady 20 m/s. A friend stands on the platform. Both watch the same falling ball. Which quantity do they measure the same?
- Nothing: each frame sees a different motion of the ball
- Its displacement in 1 s, since the clock time is shared
- Its velocity, since the ball is one object in both views
- Its acceleration: the frames differ by a steady velocity