Answer:
When there is a change in magnetic flux linkage through a loop of wire, an electromotive force is induced in the loop, according to the Faraday-Newmann-Lenz Law:

where
N is the number of turns in the loop
is the change in magnetic flux through the loop
is the time elapsed
The negative sign in the formula represents Lenz's Law, and tells us about the direction of the electromotive force.
In fact, the negative sign means that the direction of the induced emf is such that to oppose to the change in the magnetic flux that originated the induced emf.
This is a consequence of the law of conservation of energy: no energy can be created out of nowhere. In fact, when the emf is induced in the loop, electrical energy appears in the circuit; however, this electric energy cannot come out of nowhere. Instead, it is just "created" from the transformation of some other form of energy (for instance, the mechanical energy that is used to move the loop in the magnetic field, and changing its magnetic flux).
The negative sign in Lenz's Law tells exactly this: the direction of the induced emf is such that it opposes the initial change in magnetic flux that generated the induced emf, so that overall the total energy is conserved.
The cost of excavating a space of 84 ft long, 42 ft wide, and 9 ft deep is $45864
Information about the problem:
- Space long= 84 ft
- Space wide= 42 ft
- Space deep= 9 ft
- Cost by yard3 = $39/yd3
- Total cost= ?
To solve this problem, we have to state the equation using the information of the problem:
Calculating the volume of the total space:
space volume = space long * space wide * space deep
space volume = 84 ft * 42 ft * 9 ft
space volume = 31752 ft3
By converting the volume from ft3 to yd3, we have:
31752 ft3 * (0,037037 yd3 / 1 ft3) = 1176 yd3
Calculating the cost of excavating the volume space:
Total cost = space volume * cost by yard3
Total cost = 1176 yd3 * $39/yd3
Total cost = $45864
<h3>What is volume?</h3>
It is the space occupied by a body, it is calculated by multiplying its dimensions, for example: length, height and width.
Learn more about volume at: brainly.com/question/12628341
#SPJ4
Answer:


Explanation:
G = Gravitational constant = 6.67 × 10⁻¹¹ m³/kgs²
= Mass of sphere = 2000 kg
= Mass of other sphere = 2.1 kg
r = Distance between spheres
Force of gravity is given by

The gravitational force is 

The gravitational force is 