rohitju's Avatar
Hot goIITian

Joined: 13 Dec 2006
Post: 116
18 Dec 2006 13:43:23 IST
0 People liked this
1222 View Post
current electricity
Engineering Entrance , Medical Entrance , NEET , JEE Main , AIIMS , JEE Main & Advanced , Physics , Electricity

in networks of resistances,sometimes symmetry of the circiut is used. what or how  exactly does it help us in simplifying the circuit? i always end up removing the wrong resistances.

Comments (2)

rashmi_jain's Avatar

Forum Expert
Joined: 6 Dec 2006
Posts: 97
18 Dec 2006 22:30:25 IST
1 people liked this

the funda is that if the network of resistances is symmetrical,then cut it into two along the axis of symmetry
if a resistance lies completely along the axis then remove it completely.
take half of the circuit,if a resistance(r) was cut into half,then take its resistance as r/2
now calculate the net resistance of half of this circuit(say R).for this,all the resistances emanating from one point are in parallel
net resistance of the circuit will be 2R 
cvramana's Avatar

Forum Expert
Joined: 13 Nov 2006
Posts: 558
18 Dec 2006 22:40:35 IST
1 people liked this

Consider the following equation
X2 + Y2 = 10; in this equation if we interchange the variables the equation does not change. In such case we call the equation is symmetrical with respect to x and y. 
Similarly if the currents assigned in the particular resistors are interchanged the circuit should not look different. Then we say that the circuit is symmetrical about those resistors. In such cases the current does not flow in some resistors or some joints can be disjoined, so that the circuit does not alter.

Quick Reply


Some HTML allowed.
Keep your comments above the belt or risk having them deleted.
Signup for a avatar to have your pictures show up by your comment
If Members see a thread that violates the Posting Rules, bring it to the attention of the Moderator Team
Free Sign Up!
Sponsored Ads

Preparing for JEE?

Kickstart your preparation with new improved study material - Books & Online Test Series for JEE 2014/ 2015

@ INR 5,443/-

For Quick Info






Vertical Limit

Top Contributors
All Time This Month Last Week
1. Bipin Dubey
Altitude - 16545 m
Post - 7958
2. Himanshu
Altitude - 10925 m
Post - 3836
3. Hari Shankar
Altitude - 10085 m
Post - 2217
4. edison
Altitude - 10825 m
Post - 7804
5. Sagar Saxena
Altitude - 8635 m
Post - 8064
6. Yagyadutt Mishr..
Altitude - 6330 m
Post - 1958

Find Posts by Topics






Parents Corner


Fun Zone