Practice Test 12 - 4th Grade Science
20 questions. Answer them in any order, then submit to see your score and every explanation.
- For this communication problem, Yuki and Jamal want a Morse-style code for the letters A, B, and C using short and long taps. What should the pattern system include to communicate these messages?
- Chen connects a battery, wires, and a small bulb in a closed loop. The bulb lights up, but it stays off when one wire is removed. In this observation, what type of energy transfer is shown?
- For a butterfly, which structure helps it drink nectar for survival?
- Chen and Maya need silent directions during a test. Solution A uses foot taps under the desk (1="look up," 2="turn page," 3="done"). Solution B uses small sticky-note symbols (circle="look up," arrow="turn page," check="done"). Which solution would be better if materials needed must be minimal?
- When a volcano erupts near Carlos's town, what is one effect on people's daily life?
- Which environmental impact results from burning coal in a power plant for electricity?
- Jamal and Sofia need a multi-message system for 8 different classroom jobs. Solution A uses a chart of symbols (star, square, heart, circle, etc.). Solution B uses 3 bell sounds (ding, ding-ding, ding-ding-ding). Criteria: number of messages and clarity. Based on these criteria, which solution should be chosen for 8 different messages?
- When oil is drilled and transported, what environmental effect can happen if a spill occurs?
- For this design challenge, Keisha must create an emergency hand-crank light that converts motion energy to electrical energy and then to light energy, and it must light an LED for 1 minute using a generator, LED, wires, and a switch. Which design would best solve this problem?
- Keisha and Amir need an emergency alert system with three messages. Solution A uses a phone vibration pattern: short-short = "medical," long-long = "lost," short-long = "danger." Solution B uses colored cards: red = "medical," yellow = "lost," black = "danger." Criteria: conditions (must be silent) and speed. Which solution would be better if it must stay silent?
- Yuki pushed Toy Car A so it went 80 cm in 4 s, then hit still Car B. After, A went 20 cm and B went 50 cm. Which description uses evidence to explain the energy transfer?
- This model shows light travels from _____ to _____ to _____ so Keisha can see.
- Between coal and natural gas, which choice usually has more land damage from getting fuel?
- In this formation, what evidence in the layers shows forces acted after deposition?
- A tree has a trunk, a human has a skeleton, and a sunflower has a stem. What is similar about them?
- In a desert, rocks have small holes and smooth sides after many years. Which agent caused weathering?
- During quiet reading time, Maya and Chen must give directions without speaking. Solution A uses hand gestures (thumbs-up = "yes," hand flat = "stop," two fingers pointing = "go that way"). Solution B uses a desk-tap code (1 tap = "yes," 2 taps = "no," 3 taps = "stop"). Solution C uses color cards (green = "go," red = "stop," yellow = "wait"). Comparing these solutions, which works best for quiet conditions without making noise?
- Keisha calls: voice → phone changes sound to electric signal → wires → other phone → sound. Which is correct?
- After heavy rain, Sofia sees soil wash from a hillside into a muddy pile at the bottom. What evidence shows that erosion is moving earth materials?
- In a classroom demo like Newton's cradle, Fatima lifts one metal ball and lets it swing down. The hanging balls in the middle are still before the collision. After the moving ball hits, a ball on the other side may swing out. Which question asks about energy changes in this collision?