Answer:

Explanation:
Given a material with temperature coefficient of resistance <em>c</em>, the equation that relates the resistance
at temperature
and the resistance
at temperature
is

We want to double our resistance, so
, thus having:

For this T must be:


which for our values means (with
, remember to write temperature in S.I., and that for silver
):

Answer:
There are 45 turns in the secondary coil.
Explanation:
Given that,
Input potential of the lamp, 
The output potential of the lamp, 
Number of turns in primary coil, 
We need to find the number of turns needed on the secondary coil. We know that the ratio for a transformer is as follows :

So, there are 45 turns in the secondary coil.
The formation of new volcanoes and the eruption of some existing ones already.
The speed of the runner is 300 m /38 seconds. You can simplify this answer to be about 7.9 m/s
The displacement of Itzel according to the question is 6.3 miles SW
Displacement is defined as the distance moved by a body in a specified direction
Find the diagram attached
From the diagram given, we can see that AB is the displacement
To get the length AB, we will have to use the Pythagoras theorem:

From the diagram, we can also se that the direction of the displacement in the South West direction.
Hence the displacement of Itzel according to the question is 6.3 miles SW
Learn more here: brainly.com/question/19108075