Wednesday, June 29, 2011

Verify laws of Reflection using Plain Mirror Experiments with video presentation for std 10


1.  TO VERIFY THE LAWS OF REFLECTION USING A PLANE MIRROR
Aim : To verify the laws of reflection using a plane mirror.
Principle : When a ray of light is incident on a reflecting surface, it changes its direction of motion and travels in the original medium following certain laws. This phenomenon is called reflection of light.
Apparatus : Drawing board, a drawing paper (White), a plane mirror, a foot-rule, a pencil, four pins, four push pins, a protactor, a stand for the plane mirror.


Ø First of all fix the white drawing paper on the drawing board using push pins.
Pins up Paper on Wooden board
Ø First of all fix the white drawing paper on the drawing board using push pins. Place the plane mirror along with its stand and fix its position AB.
Verify Laws of Reflection using plain Mirror

Ø Now draw a line PQ which passes through the mid-point ‘P’ of AB and perpendicular to AB.
Ø PQ is called the normal to AB.
Law of Reflection Of Plain Mirror

Ø Draw a ray RP which makes some angle with the normal (PQ).
Ø Draw a ray RP which makes some angle with the normal (PQ). On the ray RP fix two pins P1 and P2 vertically with 2-3 cm separation between them. Ray RP is incident ray.
Reflection using Plain Mirror
Ø Now from the other side of PQ , (in which incident ray is not there) see the images of pins P1 and P2 fix other two pins P3 and P4 vertically so that pins P3, P4 and images P1 and P2 appears collinear at their lower ends.
To Verify Laws of Reflection using Plain Mirror

Ø Now remove the pins and the mirror. Join the marks of P3 andP4 and obtain the reflected ray PS.
Reflection by a Plain Mirror
Ø Repeat  the experiment for different angles of incidence. Measure angle of incidence and angle of reflection. Note your reading in the observations table.
Observation of Reflection of Plain Mirror
Conclusion :
Practical Uses:
We can study the laws of reflection. We can also study the images obtained by the plane mirror. We can come to know how reflection is used in various optical appliances, e.g., periscope, keleidoscope.

Video :
To Verify the Laws of Reflection using Plain Mirror