Practice Test 2 - 4th Grade Science
20 questions. Answer them in any order, then submit to see your score and every explanation.
- Maya turns on a light bulb using a wall switch. This device converts energy from ___ to ___.
- Rain starts; an earthworm comes up, a bird shelters, and a plant absorbs water. Why responses differ?
- Comparing fast and slow streams, which statement best explains why rate matters for landform change?
- A Newton's cradle has 5 same-size balls touching. When Maya lifts and releases 1 ball, how many balls will swing out on the other side?
- Chen rolled Marble A at into still Marble B; after, A was and B was . Using the data, describe how energy moved between the marbles.
- Emma turns on a flashlight with batteries. What energy transformation occurs in this device?
- Marcus talks on a corded phone: first he speaks, then the phone changes sound to an electric signal, next it moves through wires, and finally the other phone makes sound for Keisha. Where does the energy go after it leaves Marcus's voice?
- After days of rain, soil slides from a steep slope to the bottom. Which agent is moving the material?
- Tracing the information flow, which pathway ends with an observable action and not the brain?
- Yuki tested a sound-making device that changes battery energy into sound through a small speaker. It made a sound, but it was too quiet to hear from 3 meters away; the goal was to hear it from 3 meters. The battery and speaker wires looked loose during the test. Based on the results, what change would help the device work better?
- Marcus sits by a window and sees a green plant in daylight. How does he see the plant?
- In this model, what happens immediately after the brain decides to pull away? Hot stove → skin → sensory nerve → brain → motor nerve → arm muscles → pull away.
- Looking at this map, what pattern do you observe in the volcanoes around the Pacific Ocean?
- Yuki found many trilobite fossils in older layers, but coral fossils in newer layers above them. Based on these fossils, what can you infer about the water?
- Jamal's town near a river floods each spring, damaging roads and homes; what could reduce flood impacts?
- Diego's group tested a lifting device with a hand crank that changes motion energy into lifting work. It lifted a 100 g bag 20 cm, but it could not lift a 300 g bag at all. Their goal was to lift 300 g the same height. The results show the design needs more mechanical advantage. To improve the energy conversion, what should be changed?
- Maya jogged 30 meters in 15 seconds, then sprinted 30 meters in 5 seconds. Using the data, what happened to her kinetic energy when her speed increased? Use evidence.
- Fatima and Carlos need an emergency alert system for 4 needs on a field trip. Solution A uses a whistle: 1 blast="lost," 2 blasts="hurt," 3 blasts="need water," long blast="danger." Solution B uses a sign card: show red="danger," blue="need water," yellow="lost," green="hurt." Which solution works best in the dark for conditions?
- On this map, where are the Stone Mountains located?
- Carlos tested a solar-powered car that converts light energy to motion. It traveled 0.8 meters on smooth tile, but only 0.2 meters on carpet; the goal was 2 meters on both surfaces. The testing showed the wheels sink into the carpet and slow down. Based on the results, which refinement would help it move better on carpet?