Answer: P= W/t so P=50/20 =2.5 W
The resistance of a wire is given by

where

is the resistivity of the material, L the length of the wire and A its cross-sectional area.
In the problem,

and L remain the same, while A changes because the radius changes. The area is given by:

This means that if we double the radius (2r), the area becomes

And therefore, the new value of the resistance is

So, when the radius is doubled, the resistance becomes

of its original value.
Explanation:
Hi there!
Mass of the container (m) = 15000 kg
Also from the figure;
Volume of the container (V) = l*b*h
{ From figure length = 2m , breadth = 1.1m, height = 2.5m}
So,
V = (2*1.1*2.5) m³
= 5.5m³
Then;
Density (d) = m/v
= 15000/5.5
= 2727.27 kgm³
Therefore, the density is 2727.27 kgm³.
Hope it helps!
~Hello there!
Your question: Which term is defined as the change in the direction of light when it goes from one medium into a different medium?
Your answer: Refraction is the term defined as the change in the direction of the light when it goes from one medium into a different medium.
Hope this helps! :3