11th grade Plane mirrors and the law of reflection worksheet

Plane mirrors and the law of reflection

Grade 11 Science Worksheet

Circle the best answer, or write your answer on the line.

1. 1.

   A flashlight 3 m up bounces a beam off a floor mirror onto a target 1 m up, 8 m away across the floor. How far from the flashlight's foot is the bounce point, Ari?
2. 2.

   A flashlight 1 m up bounces a beam off a floor mirror onto a target 5 m up, 12 m away across the floor. How far from the flashlight's foot is the bounce point, Bo?
3. 3.

   Two plane mirrors face each other 0.6 m apart. A lamp is 0.2 m from the first. The second mirror reflects the first image. How far from the lamp is that new image, Jun?

   • 0.6 m, the gap between the mirrors
   • 2.4 m, twice the answer for the first image
   • 1.2 m, twice the 0.6 m gap
   • 0.8 m, the lamp's image in the second mirror
4. 4.

   A periscope has two parallel mirrors at 45°, 1.2 m apart along the tube. A horizontal beam enters the top. What does Kira see leaving the bottom?

   • A horizontal beam going the same way, 2.4 m lower
   • A horizontal beam going the same way, 1.2 m lower
   • A horizontal beam going back the way it came
   • A vertical beam, because the tube is vertical
5. 5.

   A camera on top of a 1.8 m pole must see the whole pole in a wall mirror. Luz moves the pole from 2 m to 4 m away. What mirror height is needed?

   • 1.8 m at both distances, the pole's full height
   • 0.45 m at 4 m: farther objects look smaller
   • 1.8 m at 4 m: the pole is twice as far
   • 0.9 m at both distances, half the pole's height
6. 6.

   Two mirrors meet at 90°. A beam reflects once off each. Milo compares the leaving beam with the entering beam. What is true for any entry angle?

   • It leaves parallel to the entering beam, going the opposite way
   • It leaves parallel to the entering beam, going the same way
   • Its direction depends on the entry angle
   • It leaves at right angles to the entering beam
7. 7.

   Two mirrors meet at 50°. A beam reflects once off each. Through what angle has Noah's beam turned from its original direction?

   • 80°, 180° − 100°
   • 130°, the supplement of the angle between the mirrors
   • 100°, twice the angle between the mirrors
   • 50°, the angle between the mirrors
8. 8.

   Ren's drone flies straight at a wall mirror at 2 m/s. How fast does the drone approach its own image?

   • 2 m/s, the drone's own speed, with the image ignored
   • 1 m/s, half the drone's speed, shared with the image
   • 4 m/s, because the image also approaches at 2 m/s
   • 0 m/s, because a virtual image is not really there to meet
9. 9.

   A drone hovers in front of a wall mirror. Tala pushes the mirror toward the drone at 0.5 m/s. How fast does the drone's image move?

   • 0 m/s, because the drone is still
   • 0.25 m/s toward the drone
   • 1.0 m/s toward the drone, twice the mirror's speed
   • 0.5 m/s toward the drone, the same as the mirror's speed
10. 10.

    A reflected beam hits a wall 3.0 m away at right angles. Zee turns the mirror 22.5°. How far does the spot move along the wall?

    • 1.24 m: tan 22.5° × 3.0 m, using the mirror's turn
    • 3.0 m: the beam turns 45°, and tan 45° = 1
    • 1.5 m: half the wall distance
    • 6.0 m: twice the wall distance