The concept required to solve this problem is linked to inductance. This can be defined as the product between the permeability in free space by the number of turns squared by the area over the length. Recall that Inductance is defined as the opposition of a conductive element to changes in the current flowing through it. Mathematically it can be described as
Here,
= Permeability at free space
N = Number of loops
A = Cross-sectional Area
l = Length
Replacing with our values we have,
Therefore the Inductance is 
No artificial ingredients
i only know that because my mom was vegan for two years
The work done to pull the sled up to the hill is given by
where
F is the intensity of the force
d is the distance where the force is applied.
In our problem, the work done is
and the distance through which the force is applied is
, so we can calculate the average force by re-arranging the previous equation and by using these data:
1). The little projectile is affected by friction all the way through the block.
Friction robs some kinetic energy.
2). The block is affected by friction as it scrapes along the top of the post.
Friction robs some kinetic energy.
3). The block is also affected by friction with the air (air resistance) as it
falls to the ground. Friction robs some kinetic energy.
Answer:
its B because we're not talking about mass even tho most people would have chosen A cuz it says mass and u they would think its apart of density but if ur testing to see density ur figuring out which object will sink and which one will float so da reason why da penny snuck it cuz da density is greater den da water and copper has a better chance of sinking den floating so dats why its B I hope dis helps :3
