Die Wissenschaft hinter alltäglichen Dingen

by Vocafy Geprüft

Englisch (USA) B1 15 Fragen Science

Entdecke, warum Eis schmilzt, Schatten wachsen und sich Alltagsgegenstände auf überraschende Weise verhalten.

1. 1. Wähle die richtige Antwort aus.

   Warum wird das Eis flüssig?

   An ice cube is left on a plate in a warm kitchen. Slowly, it melts.

   • It absorbs heat from the room.
   • It releases heat into the room.
   • The room air presses it into a liquid.

   Überlege, was wärmer ist: das Eis oder der Raum.

   Show solution

   • It absorbs heat from the room.

   Wärme fließt von wärmeren zu kälteren Dingen. Selbst kühle Raumluft kann warm genug sein, um Eis zu schmelzen.

2. 2. Fülle die Lücke aus.

   A ball rolls across a level carpet. It slows down because ___ acts against its movement.

   • gravity
   • friction
   • magnetism

   Think about the contact between the ball and the carpet.

   Show solution

   A ball rolls across a level carpet. It slows down because friction acts against its movement.

   Friction resists movement between touching surfaces. Some of the energy from the ball's movement becomes heat.

3. 3. Wähle die richtige Antwort aus.

   Warum kannst du dein Gesicht im Spiegel sehen?

   You stand in front of a mirror in a bright room.

   • It makes its own light in the shape of your face.
   • It pulls light from your eyes toward your face.
   • It sends light from your face back to your eyes.

   Ein Spiegel ändert die Richtung des Lichts.

   Show solution

   • It sends light from your face back to your eyes.

   Ein Spiegel reflektiert Licht. Seine glatte Oberfläche sorgt dafür, dass das reflektierte Licht geordnet bleibt, sodass du ein klares Bild siehst.

4. 4. Wähle die richtige Antwort aus.

   Was erzeugt den Ton?

   You pull a guitar string to one side and let it go. You hear a musical note.

   • The string heats the air as it moves.
   • The string vibrates and makes the air vibrate.
   • The string sends light waves through the air.

   Beobachte, wie sich die Saite bewegt, nachdem du sie losgelassen hast.

   Show solution

   • The string vibrates and makes the air vibrate.

   Schall breitet sich als Schwingungen durch die Luft aus. Der Korpus der Gitarre schwingt ebenfalls, wodurch der Ton lauter wird.

5. 5. Fülle die Lücke aus.

   Cooking oil and water are at the same temperature. The oil floats on top because it is ___.

   • more dense than water
   • as dense as water
   • less dense than water

   Vergleiche das Gewicht gleicher Volumina von Öl und Wasser.

   Show solution

   Cooking oil and water are at the same temperature. The oil floats on top because it is less dense than water.

   Die Dichte setzt Masse und Volumen ins Verhältnis. Eine Tasse Speiseöl wiegt weniger als eine Tasse Wasser.

6. 6. Wähle die richtige Antwort aus.

   Why is your shadow longer in the late afternoon?

   On level ground, your shadow is usually longer in the late afternoon than around noon.

   • The Sun is lower in the sky.
   • The Sun is higher in the sky.
   • The Sun is much closer to Earth.

   Think about the angle at which sunlight reaches the ground.

   Show solution

   • The Sun is lower in the sky.

   Light from a low Sun reaches the ground at a smaller angle, stretching shadows farther across it.

7. 7. Wähle die richtige Antwort aus.

   Woher kommt das Wasser auf der Außenseite?

   A dry, unbroken glass is filled with ice water. Soon, drops form on the outside. No water has spilled.

   • Water inside passes through the glass.
   • Water in the air cools and becomes liquid.
   • The ice pushes water over the top.

   Luft enthält Wasser, auch wenn du es nicht sehen kannst.

   Show solution

   • Water in the air cools and becomes liquid.

   Diese Veränderung nennt man Kondensation. Sie führt auch dazu, dass sich nach einer heißen Dusche Tropfen auf einem Badezimmerspiegel bilden.

8. 8. Fülle die Lücke aus.

   Two shirts are made of the same fabric and have the same thickness. In direct sunlight, the black shirt usually gets hotter because it ___.

   • reflects more of the sunlight
   • absorbs none of the sunlight
   • absorbs more of the sunlight

   Think about whether the light bounces away or enters the material.

   Show solution

   Two shirts are made of the same fabric and have the same thickness. In direct sunlight, the black shirt usually gets hotter because it absorbs more of the sunlight.

   Absorbed sunlight adds heat to the fabric. White surfaces reflect more sunlight, which can help them stay cooler.

9. 9. Wähle die richtige Antwort aus.

   Was zieht die Haare zum Luftballon hin?

   You rub a balloon against a sweater. When you hold it near your hair, some hairs rise toward it.

   • An electric force.
   • A magnetic force.
   • Extra air pressure.

   Durch Reiben können winzige geladene Teilchen zwischen Materialien übertragen werden.

   Show solution

   • An electric force.

   Durch Reiben erhält der Luftballon eine elektrische Ladung. Er kann auch kleine Papierstücke anziehen, obwohl sie nicht aus Metall sind.

10. 10. Wähle die richtige Antwort aus.

    Why does your skin feel cooler as your hands dry?

    Your hands are wet. As they dry in the air, your skin feels cool.

    • The water gives extra heat to your skin.
    • The water becomes tiny pieces of ice.
    • The water takes heat from your skin as it becomes a gas.

    Changing liquid water into a gas requires energy.

    Show solution

    • The water takes heat from your skin as it becomes a gas.

    This process is called evaporation. Sweat cools your body in the same way when it evaporates.

11. 11. Wähle die richtige Antwort aus.

    Warum kann das Erwärmen des Deckels das Öffnen erleichtern?

    A metal lid is stuck on a glass jar. You run warm water over the lid.

    • The metal lid becomes lighter.
    • The metal lid expands a little.
    • The metal lid shrinks a little.

    Überlege, wie sich die Größe von Metall verändert, wenn es wärmer wird.

    Show solution

    • The metal lid expands a little.

    Die meisten Metalle dehnen sich beim Erwärmen aus. Schon eine geringe Zunahme der Deckelbreite kann seinen festen Sitz auf dem Glas lockern.

12. 12. Wähle die richtige Antwort aus.

    Wie hilft die eingeschlossene Luft dabei, dass ein heißes Getränk warm bleibt?

    A cup has two walls with still air trapped between them.

    • The air slows the movement of heat out of the cup.
    • The air produces new heat inside the cup.
    • The air carries heat quickly through the walls.

    Ruhende Luft leitet Wärme nur schlecht weiter.

    Show solution

    • The air slows the movement of heat out of the cup.

    Eingeschlossene Luft wirkt isolierend: Sie verlangsamt den Wärmeverlust. Viele warme Jacken schließen ebenfalls Luft zwischen ihren Fasern ein.

13. 13. Fülle die Lücke aus.

    Two backpacks weigh the same, but one has wider shoulder straps. The wider straps can feel more comfortable because they spread the weight over ___.

    • a smaller area of your shoulders
    • the same area of your shoulders
    • a larger area of your shoulders

    Compare how a thin string and a wide belt press against your hand.

    Show solution

    Two backpacks weigh the same, but one has wider shoulder straps. The wider straps can feel more comfortable because they spread the weight over a larger area of your shoulders.

    The same force spread over a larger area creates less pressure. Wider straps reduce pressure without reducing the backpack's weight.

14. 14. Wähle die richtige Antwort aus.

    Why can potatoes take longer to cook in boiling water there?

    High in the mountains, water boils at a lower temperature than it does at sea level.

    • Water stops transferring heat once it boils.
    • The water is cooler, even while it is boiling.
    • The bubbles in the boiling water prevent heat from reaching the potatoes.

    Boiling water is not always at the same temperature.

    Show solution

    • The water is cooler, even while it is boiling.

    Lower air pressure allows water to boil at a lower temperature. Food can therefore cook more slowly, even with plenty of bubbles.

15. 15. Wähle die richtige Antwort aus.

    What makes the bottle's sides bend inward?

    A thin plastic bottle full of warm air is tightly closed. As it cools in a cold room, its sides bend inward.

    • The air inside pushes harder than the air outside.
    • The air pressure is equal inside and outside.
    • The air outside pushes harder than the air inside.

    The bottle is closed, so no more air can enter as the trapped air cools.

    Show solution

    • The air outside pushes harder than the air inside.

    Cooling lowers the pressure of the trapped air. Outside air then pushes the flexible sides inward.