Answer:

Explanation:
The electric field produced by a single point charge is given by:

where
k is the Coulomb's constant
q is the charge
r is the distance from the charge
In this problem, we have
E = 1.0 N/C (magnitude of the electric field)
r = 1.0 m (distance from the charge)
Solving the equation for q, we find the charge:

Answer:
Current, I = 1000 A
Explanation:
It is given that,
Length of the copper wire, l = 7300 m
Resistance of copper line, R = 10 ohms
Magnetic field, B = 0.1 T

Resistivity, 
We need to find the current flowing the copper wire. Firstly, we need to find the radius of he power line using physical dimensions as :




r = 0.00199 m
or

The magnetic field on a current carrying wire is given by :



I = 1000 A
So, the current of 1000 A is flowing through the copper wire. Hence, this is the required solution.
Answer:
1 ) Electrons are less massive than than atomic nuclei.
Explanation:
A positively charged body tends to attract negatively charged particle and repel positively charged particle. Neutral body consists of atoms which contain both positively charged particles ( electrons ) and negatively charged particles ( protons ). Electrons are small and light in weight . Both electrons and protons experience equal and opposite force by an external charged body but shift in electron is more because of their being comparatively lighter. So the body gets polarized due to uneven distribution of charge. This results into body getting attracted through the process of induction.
PART A)
horizontal distance that will be moved = 14 m
Height of the fence = 5.0 m
height from which it is thrown = 1.60 m
angle of projection = 54 degree
So here we can say that stone will travel vertically up by distance

now we will have displacement in horizontal direction

now we know that


now we will have


also for y direction


now from the two equations we will have




now from above equations


So the minimum speed will be 13.2 m/s
Part B)
Total time of the motion after which it will land on the ground will be "t"
so its vertical displacement will be

now we will have




Now the time after which it will reach the fence will be t1 = 1.8 s
so total time after which it will fall on other side of fence


now the displacement on the other side is given as



Answer:
The resulting, needed force for equilibrium is a reaction from a support, located at 2.57 meters from the heavy end. It is vertical, possitive (upwards) and 700 N.
Explanation:
This is a horizontal bar.
For transitional equilibrium, we just need a force opposed to its weight, thus vertical and possitive (ascendent). Its magnitude is the sum of the two weights, 400+300 = 700 N, since weight, as gravity is vertical and negative.
Now, the tricky part is the point of application, which involves rotational equilibrium. But this is quite simple if we write down an equation for dynamic momentum with respect to the heavy end (not the light end where the additional weight is placed). The condition is that the sum of momenta with respect to this (any) point of the solid bar is zero:

Where momenta from weights are possitive and the opposed force creates an oppossed momentum, then a negative term. Solving our unknown d:

So, the resulting force is a reaction from a support, located at 2.57 meters from the heavy end (the one opposed to the added weight end).