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Seeing is believing? Les illusions d'optique (5e)

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an optical illusionune illusion d'optique
Which line looks longer?Quelle ligne paraît la plus longue ?
They're exactly the same length!Elles ont exactement la même longueur !
It seems to move.Ça semble bouger.
Your brain is tricked.Ton cerveau est trompé.
It looks like a vase... or two faces!On dirait un vase... ou deux visages !

Une illusion d'optique trompe notre cerveau : on croit voir quelque chose qui n'est pas vrai. Deux lignes de même longueur paraissent différentes, une image immobile semble bouger, un dessin montre un vase ou deux visages selon la façon dont on le regarde. Pour décrire une impression : It looks + adjectif (It looks longer), It looks like + nom (It looks like a vase), It seems to + verbe (It seems to move).

Mise en situation : le cours de sciences

Teacher : Look at these two lines. Which one looks longer?
Regardez ces deux lignes. Laquelle paraît la plus longue ?
Hugo : The top one, definitely!
Celle du haut, sans aucun doute !
Teacher : Let's measure them... They're exactly the same length!
Mesurons-les... Elles ont exactement la même longueur !
Lily : No way! My brain was tricked!
Pas possible ! Mon cerveau a été trompé !
Teacher : Now look at this picture. What can you see?
Maintenant, regardez cette image. Que voyez-vous ?
Hugo : It looks like a vase... no, wait, it's two faces! And this circle seems to move!
On dirait un vase... non, attends, ce sont deux visages ! Et ce cercle semble bouger !

À retenir

  • an optical illusion, a line, a picture, a circle, the brain, the eyes, length.
  • It looks + adj. / It looks like + nom / It seems to + verbe ; Which one looks longer? the same length.

Exercice 1 : Les illusions d'optique : exercice 1 (QCM)

  1. « une illusion d'optique »
    1. an optical allusion
    2. an optical illusion
    3. an optic illusion of
  2. « Elle paraît plus longue. »
    1. It look longer.
    2. It looks like longer.
    3. It looks longer.
  3. « On dirait un vase. »
    1. It looks a vase.
    2. It looks like a vase.
    3. It likes a vase.
  4. « Ça semble bouger. »
    1. It seems to move.
    2. It seems move.
    3. It seem to moving.
  5. « la même longueur »
    1. the same lenght
    2. the same long
    3. the same length
  6. « Ton cerveau est trompé. »
    1. Your brain tricked is.
    2. Your brain is tricked.
    3. Your brain is trick.
  7. « Mesurons-les. »
    1. Let's measure them.
    2. Let's measure they.
    3. Let measure them.
  8. « sans aucun doute »
    1. definitely
    2. define
    3. definitively of
  9. « Pas possible ! »
    1. No way!
    2. No why!
    3. Not way!
  10. « Laquelle ? »
    1. What one of?
    2. Which one?
    3. Witch one?

Exercice 2 : Les illusions d'optique : exercice 2 (à compléter)

  1. Which one looks .......................... ?
  2. They're exactly the same .......................... !
  3. My brain was .......................... !
  4. It looks .......................... a vase.
  5. This circle .......................... to move.
  6. Let's .......................... them.
  7. What can you .......................... ?
  8. No .......................... !
  9. It's two .......................... !
  10. an optical ..........................

Exercice 3 : Les illusions d'optique : mise en situation

  1. Laquelle paraît la plus longue ?
    1. Which one looks longer?
    2. Witch one looks longer?
    3. Which one looks like longer?
  2. Celle du haut, sans aucun doute.
    1. The up one, definitely!
    2. The top one, definitely!
    3. The top one, definitively!
  3. Elles ont la même longueur.
    1. There exactly the same length!
    2. They're exactly the same long!
    3. They're exactly the same length!
  4. Mon cerveau a été trompé.
    1. My brain tricked!
    2. My brain was tricked!
    3. My brain is tricked yesterday!
  5. Que voyez-vous ?
    1. What you can see?
    2. What can you sea?
    3. What can you see?
  6. On dirait un vase.
    1. It looks like a vase.
    2. It like a vase.
    3. It looks a vase.
  7. Ce cercle semble bouger.
    1. This circle seem to move!
    2. This circle seems moving!
    3. This circle seems to move!
  8. Les couleurs paraissent différentes.
    1. The colours look different.
    2. The colours look like different.
    3. The colours looks different.
  9. Ça a l'air facile, mais c'est difficile.
    1. It look easy, but it's difficult.
    2. It looks easy, but it's difficult.
    3. It looks like easy, but it's difficult.
  10. Tu n'en crois pas tes yeux !
    1. I can't believe my ice!
    2. I can't believe my eyes!
    3. I don't can believe my eyes!

Corrigé

Exercice 1

1. b) an optical illusion · 2. c) It looks longer. · 3. b) It looks like a vase. · 4. a) It seems to move. · 5. c) the same length · 6. b) Your brain is tricked. · 7. a) Let's measure them. · 8. a) definitely · 9. a) No way! · 10. b) Which one?

Exercice 2

1. longer · 2. length · 3. tricked · 4. like · 5. seems · 6. measure · 7. see · 8. way · 9. faces · 10. illusion

Exercice 3

1. a) Which one looks longer? · 2. b) The top one, definitely! · 3. c) They're exactly the same length! · 4. b) My brain was tricked! · 5. c) What can you see? · 6. a) It looks like a vase. · 7. c) This circle seems to move! · 8. a) The colours look different. · 9. b) It looks easy, but it's difficult. · 10. b) I can't believe my eyes!