Speeding up, slowing down and turning
Grade 8 Science Worksheet - Challenge Me

Circle the best answer.
Ari's sled slides right across flat snow and slows down. Which pair of arrows fits the sled?
- Velocity left, net force right
- Velocity right, net force left
- Velocity right, net force right
- Velocity right, net force up the page
A puck slides north on ice and curves to the west at a steady speed. Which pair of arrows fits the puck at the start of the curve, Bo?
- Velocity north, net force west
- Velocity west, net force north
- Velocity north, net force north
- Velocity north, no net force
Esme's toy car circles a round track at a steady speed. At the top of the circle it moves right. Which pair of arrows fits it there?
- Velocity right, net force down toward the center
- Velocity right, net force up, away from the center
- Velocity right, net force right
- Velocity right, no net force
The Moon circles Earth at about 1 km/s, its speed changing little. Is the Moon accelerating, Jun?
- Yes: its direction keeps changing
- No: nothing pulls on it in space
- Yes: it is speeding up
- No: its speed hardly changes
A car drives once around a circular track at a steady 15 m/s and stops where it started. Did it accelerate while circling, Kira?
- No: its speed stayed 15 m/s
- No: it ended where it began
- Yes, the whole time it turned
- Yes, but just at the start
Luz's bus slows down, turns a corner, then speeds up. During which parts is the bus accelerating?
- All three parts
- While slowing and speeding up, not turning
- None: a bus is too big
- Only while speeding up
Noah says a fast train cruising straight at 80 m/s has a huge acceleration. Agree or disagree?
- Disagree: its velocity is not changing
- Agree: a long train has more acceleration
- Disagree: trains can't accelerate
- Agree: faster means more acceleration
Pia says a ball rolling at a steady speed around a curved track has zero acceleration. Agree or disagree?
- Disagree: its direction changes
- Agree: the speed stays the same
- Disagree: it is slowing down
- Agree: curves don't count
Ren's distance-time line is straight and rising. Is the object accelerating?
- No: it moves at a steady speed
- Yes: it is slowing down
- Yes: its distance keeps growing
- No: it is stopped
Zee's distance-time line rises but bends flatter each second. What is the object doing?
Distance-time graph (example data). Time (s) across, 0 to 4, a mark every 1 s. Distance from start (m) up, 0 to 16, a mark every 4 m. The line passes through (0 s, 0 m), (1 s, 7 m), (2 s, 12 m), (3 s, 15 m), (4 s, 16 m), joined by a smooth curve that gets flatter. Distance-time graph (example data). Time (s) across, 0 to 4, a mark every 1 s. Distance from start (m) up, 0 to 16, a mark every 4 m. The line passes through (0 s, 0 m), (1 s, 7 m), (2 s, 12 m), (3 s, 15 m), (4 s, 16 m), joined by a smooth curve that gets flatter. Distance-time graph (example data) 0 1 2 3 4 0 4 8 12 16 Time (s) Distance from start (m) - Slowing down
- Moving at a steady speed
- Speeding up: its distance still grows
- Moving back toward the start