Answer:
An Object is positively charged if it has more Positive Electrons in that object
Answer:
The strength of magnetic field is 0.2 Tesla.
Explanation:
Data from the question is
Length (L) of wire ; L=0.10 m
Current in wire ; I= 2.0 A
Force on wire ; F = 0.04 N
Angle = Right angle So, 

Now ,
We have to find the magnetic Field strength (B)
For this formula for Force on wire in magnetic field is

Further modified as

Now insert values in the formula


So, the strength of magnetic field is 0.2 Tesla.
Refer to the diagram shown below.
μ = the coefficient of dynamic friction between the crate and the ramp.
1. The applied force of F acts over a distance, d.
The work done is F*d.
2. The component of the weight of the crate acting down the ramp is
mg sin(30) = 0.5mg.
The work done by this force is 0.5mgd.
3. The normal force is N = mgcos(30) = 0.866mg.
This force is perpendicular to the ramp, therefore the work done is zero.
4. The frictional force is μN = μmgcos(30) = 0.866μmg.
The work done by the frictional force is 0.866μmgd.
5. The total force acting on the crate up the ramp is
F - mgsin(30) - μmgcos(30) = F - mg(0.5 - 0.866μ)
6. The work done on the crate by the total force is
d*(F - 0.5mg - 0.866μmg)
8 phases. I really hope you get the right answer!