x Turn on thread page Beta
 You are Here: Home >< Physics

# Power and intensity question!? watch

1. (Original post by Danny.L)
Yeah, I showed my teacher my working today, he said it wa great. However I could get the intensity directly via the method you used. He went a step further and showed I1R1^2 = K I2R2^2 = k
therefore they equal each other.
He also spotted what I had done wrong for my working by multiplying 1400 Wm-2 by (1.5 *10^11)^2. That was finding the intensity 1m away from the centre of the sun, but we wanted it at the surface, so needed to then divide by (7 * 10*)^2 (which is radius of sun squared). I think that's correct! How does that sound to you?
sounds right - obviously you could use the same methods to get the intensity at neptune or any other r that is greater than the sun's radius.

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: January 30, 2015
Today on TSR

Is it worth it?

### How do you cope with exam stress?

Poll

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE