Plane mirrors and the law of reflection
Grade 11 Science Worksheet
Circle the best answer, or write your answer on the line.
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?
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?
A flashlight 4 m up bounces a beam off a floor mirror onto a target 1 m up, 10 m away across the floor. How far from the flashlight's foot is the bounce point, Esme?
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?
- 0.8 m, the lamp's image in the second mirror
- 2.4 m, twice the answer for the first image
- 1.2 m, twice the 0.6 m gap
- 0.6 m, the gap between the mirrors
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
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?
- 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
- 1.8 m at both distances, the pole's full height
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 at right angles to the entering beam
- Its direction depends on the entry angle
- It leaves parallel to the entering beam, going the same way
- It leaves parallel to the entering beam, going the opposite way
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°
- 100°, twice the angle between the mirrors
- 50°, the angle between the mirrors
- 130°, the supplement of the angle between the mirrors
A lamp sits between two hinged mirrors set 60° apart. How many images of the lamp does Pia's camera see?
- 2 images, one in each mirror
- 6 images: 360° ÷ 60°, forgetting to remove the lamp itself
- 3 images, the number for mirrors at 90°
- 5 images: 360° ÷ 60° − 1
Ren's drone flies straight at a wall mirror at 2 m/s. How fast does the drone approach its own image?
- 1 m/s, half the drone's speed, shared with the image
- 0 m/s, because a virtual image is not really there to meet
- 2 m/s, the drone's own speed, with the image ignored
- 4 m/s, because the image also approaches at 2 m/s