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collision – n. an act of colliding, such as a crash in which two or more things or people hit each other
bang – n. a sudden, loud noise
compact – adj. closely or firmly joined together
calculation – n. an estimate or prediction
ripple – n. something that passes or spreads through or over someone or something; a shape having small waves
detector – n. a device that can tell if a substance or object is present; a device that measures the presence of something
thud – n. a loud sound made especially when a heavy object hits something
