Weeds are very important agronomically because they reduce the yield of crops in three ways: by competing with the crop for water, light and nutrients, by interfering with crop harvest, and by contaminating harvested products with weed seeds and toxins. Weeds can reduce yield up to 50% and are responsible for millions of dollars in crop losses each year.
It’s biotic factor would be competition as Competition can be defined as an interaction between organisms or species, in which the fitness of one is lowered by the presence of another.
Johannes Kepler- he did it by observing the ‘Tycho Brahe’. His 3rd law was published 10 years later to his first two laws.
Answer:
- The distance between the charges is 5,335.026 m
Explanation:
To obtain the forces between the particles, we can use Coulomb's Law in scalar form, this is, the force between the particles will be:

where k is Coulomb's constant,
and
are the charges and d is the distance between the charges.
Working a little the equation, we can take:


And this equation will give us the distance between the charges. Taking the values of the problem

(the force has a minus sign, as its attractive)




And this is the distance between the charges.
Answer:
-0.912 m/s
Explanation:
When the package is thrown out, momentum is conserved. The total momentum after is the same as the total momentum before, which is 0, since the boat was initially at rest.

where
are the mass of the child, the boat and the package, respectively.
are the velocity of the package and the boat after throwing.



Answer:
P = 1000000[Pa] = 1000 [kPa]
Explanation:
To solve this problem we must use the definition of pressure, which is equal to the relationship of force over area.

where:
P = pressure [Pa] (units of pascals)
F = force = 100 [N]
A = area = 100 [mm²]
But first we must convert the units from square millimeters to square meters.
![A=100[mm^{2}]*\frac{1^{2} m^{2} }{1000^{2}mm^{2} } =0.0001[m^{2} ]](https://tex.z-dn.net/?f=A%3D100%5Bmm%5E%7B2%7D%5D%2A%5Cfrac%7B1%5E%7B2%7D%20m%5E%7B2%7D%20%7D%7B1000%5E%7B2%7Dmm%5E%7B2%7D%20%20%7D%20%3D0.0001%5Bm%5E%7B2%7D%20%5D)
Now replacing:
![P=100/0.0001\\P=1000000[Pa]](https://tex.z-dn.net/?f=P%3D100%2F0.0001%5C%5CP%3D1000000%5BPa%5D)