Concave Convex concave side convex side Concave Spherical

Concave

Convex

concave side convex side

Concave Spherical Mirrors principle axis C C = Center of Curvature R = Radius of Curvature (axis of symmetry) R Parallel Rays (distant object): C F = focal point f = focal length F f f=½R Concave mirror

Spherical Aberration Because of the spherical shape of the mirror, the outer rays don’t reflect through the focal point: F This creates a blurry image

Convex Spherical Mirrors C R Web Link: Spherical mirrors and lenses Parallel Rays (distant object): Since it’s behind the mirror F f C f = -½ R Convex mirror

Curved Mirrors applications

Hot in the City: The Walkie Talkie building is taking a lot of heat. A building in London's financial district has been blamed for cars melting on the street. The allegations were made on the business website City AM (via the UK Telegraph): The Walkie Talkie skyscraper in the City has caused extensive damage to a Jaguar parked on a nearby street - as other drivers come forward to say it has also melted parts of their vehicles. As revealed in City AM last week, the building's unusual shape is reflecting an ultra bright light onto Eastcheap, with those unlucky enough to park below finding the beam is causing serious damage. Martin Lindsay, director of a tiling company, said he was distraught to see the warped panels along the side of his high-spec Jaguar XJ. He said: "They're going to have to think of something. I'm gutted. How can they let this continue? "

Weapon of Light Over 2000 years ago Archimedes is said to have used “burning mirrors” as a weapon.

Concave mirrors focused light on attacking Roman galleys caused them to catch alight.

Power of the Press 1882

Trough Collectors

Trough collectors that do not move to follow the sun can reach temperatures of 300 o. C

This fixed mirror focuses light onto a 45 cm 2 target Focal point is in the tower

This combination of mirrors focuses the light 12 000 times and produces temperatures up to 3 800 o. C

Power Tower 2 000 mirrors reflect onto a solar power to produce steam.

Satellite communication. A transmitter dish has the transmitter at the focus which generates a parallel, directional beam.

At the other end a dish concentrates the weak signals onto the focus (where a receiver is placed).

Transmitter Receiver

Reproductive Aid Some high alpine flowers follow the sun as it crosses the sky.

Their petals focus the light so that inside the flower is up to 10 o. C warmer compared with its surroundings.

Concave mirrors can focus light… Concave mirrors can magnify an image … Convex mirrors can reduce an image…

Dentists use concave mirrors to give an enlarged view of our teeth

Make-up and Shaving mirrors are concave to give an enlarged image.

Plane Mirror Small Image Convex Mirror

Side view mirrors are convex mirrors which give a smaller image. This increases the field of view enabling the driver to see more objects behind the car.

They can also be used to help with parking etc

Security mirrors enable retailers to see what’s happening in their shops.