Answer:
Correct answer is option D
- Wire is on the cylinder axis and carries current i in the direction opposite to that of the current in the shell
Explanation:
- It cannot be Option E, because the magnetic field outside the wire would not be 0 due to the current carried by the conductor
-Also, the parallel wire cannot carry current in the same direction because, that would amplify the magnetic field created by the outer cylinder (since B is dir. proportional to the current) -and now, that leaves only option C and D. If, it is Option C, then that means one side of the cylinder would be more closer to the parallel wire than the other, so there would be different B fields on the two opposite sides of the cylinder. So, that means the answer is option D.
The Answer Is A
Hope This Helps !
Answer:
C is the right answer.
Body massager uses electrical energy to move back and forth. In this sense, a motor is being used for the operation
Answer:
27 blocks
Explanation:
First, the expression to use here is the following:
P = F/A
Where:
P: pressure
F: Force exerted
A: Area of the block.
Now , we need to know the number of blocks needed to exert a pressure that equals at least 2 atm. To know this, we should rewrite the equation. We know that certain number of blocks, with the same weight and dimensions are putting one after one over the first block, so we can say that:
P = W/A
P = n * W1 / A
n would be the number of blocks, and W1 the weight of the block.We have all the data, and we need to calculate the area of the block which is:
A = 0.2 * 0.1 = 0.02 m²
Solving now for n:
n = P * A / W1
The pressure has to be expressed in N/m²
P = 2 atm * 1.01x10^5 N/m² atm = 2.02x10^5 N/m²
Finally, replacing all data we have:
n = 2.02x10^5 * 0.02 / 150
n = 26.93
We can round this result to 27. So the minimum number of blocks is 27.
