Reflection☄️
- The normal point on a mirror is reflected perpendicularly
- For a light ray reflected by a mirror :
Angle of incidence = angle of reflection
![broken image](http://custom-images.strikinglycdn.com/res/hrscywv4p/image/upload/c_limit,fl_lossy,h_9000,w_1200,f_auto,q_auto/4979856/438095_89555.png)
Curved mirrors
☞The principal focus on a concave mirror is the point where parallel rays are focused to by the mirror.
☞A concave mirror forms:
- A real inverted image if the object is beyond the principal focus of the mirror.
- A enlarged,upright virtual image if the object is between the mirror and the principal focus.
☞A convex mirror always forms a virtual image of an object.
![broken image](http://custom-images.strikinglycdn.com/res/hrscywv4p/image/upload/c_limit,fl_lossy,h_9000,w_1200,f_auto,q_auto/4979856/730306_844599.jpg)
A concave mirror when the object is place beyond the point of curvature. The image formed is real and inverted.
![broken image](http://custom-images.strikinglycdn.com/res/hrscywv4p/image/upload/c_limit,fl_lossy,h_9000,w_1200,f_auto,q_auto/4979856/370730_132736.jpg)
A concave mirror when the object is placed betweenthe mirror and the focal point. The image formed in enlarged, upright andvirtual.
Refraction 🧺
Refraction of light is the change of direction of a light ray when it crosses a boundary between two transparent substances.
For I/GCSE Physics, refraction depends on the speed.🧑🏻🔬
If the speed is reduced, refraction is towards the normal (e.g. air to glass).
If the speed is increased, refraction is away from the normal (e.g. glass to air).
![broken image](http://custom-images.strikinglycdn.com/res/hrscywv4p/image/upload/c_limit,fl_lossy,h_9000,w_1200,f_auto,q_auto/4979856/150908_155673.jpg)
Example on refraction-Lenses👓
- A real image is formed by a converging lens if the object is further away from the principal focus.
- A virtual image is formed by a diverging lens and by a converging lens if the object is nearerthan the principal focus.
There are two lenses in I/GCSE Physics
![broken image](http://custom-images.strikinglycdn.com/res/hrscywv4p/image/upload/c_limit,fl_lossy,h_9000,w_1200,f_auto,q_auto/4979856/512267_280439.jpg)
1.A converging lens
- The principle ray is parallel to the axis and is refracted through f.
- The central ray passes straight through the centre of the lens.
- The focal ray passes through f and is refracted parallel to the axis.
![broken image](http://custom-images.strikinglycdn.com/res/hrscywv4p/image/upload/c_limit,fl_lossy,h_9000,w_1200,f_auto,q_auto/4979856/446219_466330.png)
2.A diverging lens
The image is upright, virtualand smaller than the object.
That's the end of reflection and refraction
![broken image](http://custom-images.strikinglycdn.com/res/hrscywv4p/image/upload/c_limit,fl_lossy,h_9000,w_1200,f_auto,q_60/4979856/518098_116923.gif)
Drafted by Yoko Mak(Physics)