Answer:
Current, I = 3.57A
Explanation:
A current of I amperes means that I Coulombs of charge flows through the conductor (heating coil) per second.
Therefore, in time t, the total charge (Q) passing through any point in which the current (C) flows will be given by the equation;
Q = It
Where; Q is the charge in coulombs; I is the current in amperes; t is the time in seconds.
From the question, we were given the following parameters;
Q = 25C, t= 7secs and I =?
From the equation, Q = It
We make current, I the subject of formula;
Thus, I = Q/t
Substituting into the equation;
I = 25/7
I = 3.57Amp.
Answer:
C. Copper
Explanation:
F = Force on string
= Intial length of string
A = Area of string
E = Young's modulus of material
Change in length is given by

It can be seen that the change in length is inversely proportional to the Young's modulus of the material.
Here




So, copper will stretch the least.
Answer:
the path the object follows is called its trajectory so A. trajectory
At 0.1m, the restoring force would be 25 Newtons. It would probably not be possible to stretch to 5 meters because that would cause a restoring force of 1250 Newtons.