1) Sounds are made from ________. a) vibration b) circuit 2) _______ are components of the circuit. a) lamp, wires b) lamp, battery, wires 3) We use the _______to break the circuit a) lamp b) switch 4) There is no sound in space. a) True b) False 5) When the switch is (on) a) the electricity flow b) the electricity does'nt flow 6) Sounds more than ____dB damage our ears a) 120 b) 90 7) A group of cells is a ______. a) circuit b) battery 8) One way of connecting wires is: a) touching bare wires b) using a lamp 9) The circuit works when it is _____ a) complete b) not complete 10) We can use ______ to prevent hearing the noise. a) speakers b) ear defenders 11) We call unwanted sounds ______ a) vibration b) noise 12) We can use circuits in ______ a) books b) lights at home 13) When we add more light bulbs we have ______ a) more light b) less light 14) Sound travels in the gas, solid, and liquid a) True b) False 15) We measure the loudness of sounds using the_____ a) sound level meter b) ears

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