Energy Evidence at the Winter Tailor Shop

An Afternoon at the Tailor Shop

Snow covered the town sidewalks when Imani's science club visited a tailor shop. Before customers arrived, the club compared equipment for two fitting booths. Kit A had a clear plastic screen, a small battery lamp, and a bare water bottle. Kit B had a thick cloth screen, a matching lamp, and a matching bottle with a felt sleeve. An adult checked the equipment. The club used low-voltage batteries, not wall outlets.

First, Imani listened inside each booth while a small speaker played in the aisle. For both tests, the speaker was two meters from her listening position. The club kept the tune and volume setting the same. Imani heard the tune through the clear screen and through the cloth screen. When the speaker was switched off, she stopped hearing the tune in either booth.

Next, the club placed a white card inside each booth. Each lamp shone toward a card one meter away, with the booth screen between them. A bright patch appeared behind the clear screen. No bright patch appeared behind the cloth screen. The club lifted the cloth screen, and a patch appeared on that card. They lowered the cloth, and the patch disappeared. The lamps stayed switched on and aimed at the cards throughout the test.

For the bottle comparison, an adult prepared two sealed plastic bottles containing equal amounts of warm water. Both began at 30°C. The club put them side by side on one counter, away from sunlight and the lamps. The room stayed at 18°C. Bottle A was bare; bottle B wore its felt sleeve. The bottles and amounts of water matched. The sleeve was the changed condition. The club measured the water temperatures again after 15 minutes. The graph shows their results.

Finally, the club checked the lamps without the booth screens. Each battery was connected by wires to a lamp one meter away. Lamp A shone with its switch closed. Lamp B was dark with its switch open, then shone when the switch closed. Covering battery B with a cardboard box left its lamp shining. An adult then disconnected one wire from battery B, and its lamp went dark. Reconnecting that wire made the lamp shine again.