Answer:
(a) 0.345 T
(b) 0.389 T
Solution:
As per the question:
Hall emf, 
Magnetic Field, B = 0.10 T
Hall emf, 
Now,
Drift velocity, 

Now, the expression for the electric field is given by:
(1)
And

Thus eqn (1) becomes
where
d = distance
(2)
(a) When 

(b) When 

B. sent through the atmosphere
If the desk doesn't move, then it's not accelerating.
If it's not accelerating, then the net force on it is zero.
If the net force on it is zero, then any forces on it are balanced.
If there are only two forces on it and they're balanced, then they have equal strengths, and they point in opposite directions.
So the friction on the desk must be equal to your<em> 245N</em> .
Answer:
F=ma is the relationship where, F is force, m is mass and a is acceleration.
Newton's second law states that the unbalanced force applied to the object accelerates the object which is directly proportional to the force and inversely to the mass.
If we apply force to a toy car then It will accelerate.
This is how Newton's second law of motion is verified.
Answer:
Explanation:
They need a galvanic difference. Or saying that less technically, they need to have different electron attraction, so that one can collect electrons (oxidation/reduction) and flow current from the other. :)