Explain the difference between reversible and irreversible

A 0.210-kg metal rod carrying a current of 11.0 A glides on two horizontal rails 0.490 m apart. If the coefficient of kinetic fr

sergij07 [2.7K]

Answer:

The magnetic field is $B = 0.0764 \ T$

Explanation:

From the question we are told that

The mass of the metal is $m = 0.210 \ kg$

The current is $I = 11.0 \ A$

The distance between the rail(length of the rod ) is $d = 0.490 \ m$

The coefficient of kinetic friction is $\mu_k = 0.200$

Generally the magnetic force is mathematically represented as

$F_b = B * I * d$

Given that the rod is moving at a constant velocity, it

=> $F_b = F_k$

Where $F_k$ is the kinetic frictional force which is mathematically represented as

$F_k = \mu_k * m * g$

So

$B * I * d = \mu_k * m * g$

=> $B = \frac{\mu_k * m * g}{I * d }$

substituting values

=> $B = \frac{0.200 * 0.210 * 9.8 }{ 11 * 0.490 }$

=> $B = 0.0764 \ T$

3 0

3 years ago

A trout was swimming in a river. The trout swam 7,000centimeters directly upstream at a constant velocity. It swam that distance

Mars2501 [29]

Answer:

10000

Explanation:

7 0

3 years ago

Read 2 more answers

What region of the atom determines the volume of the atom

NeX [460]

Hello kiddio!

Most of the mass of atom is in a dense positively charged nucleus. Most of the volume of an atom is in an empty space in which negatively charged electrons move around the nucleus.

Have a nice day

3 0

4 years ago

A person sits on a freely spinning lab stool that has no friction in its axle. When this person extends her arms, A. her moment

Andrei [34K]

Answer:

C. her moment of inertia increases and her angular speed decreases

D. her moment of inertia increases and her angular speed decreases

Explanation:

The moment of inertia of a body is the sum of the products of an increment of mass and the square of its distance from the center of rotation. When a spinning person extends her arms, part of her mass increases its distance from the center of rotation, so increases the moment of inertia.

The kinetic energy of a spinning body is jointly proportional to the moment of inertia and the square of the angular speed. Hence an increase in moment of inertia will result in a decrease in angular speed unless there is a change in the rotational kinetic energy.

This effect is used by figure skaters to increase their spin rate by drawing their arms and legs closer to the axis of rotation. Similarly, they can slow the spin by extending arms and legs.

When the person extends her arms, her moment of inertia increases and her angular speed decreases.

_____

Note to those looking for a letter answer

Both choices C and D have identical (correct) wording the way the problem is presented here. You will need to check carefully the wording in any problem you may think is similar.

3 0

4 years ago

A simple hydraulic lift is made by fitting a piston attached to a handle into a 3.0-cm diameter cylinder. The cylinder is connec

stiv31 [10]

Answer:

Approximately $3.1 \times 10^4 \; \rm N$ (assuming that the acceleration due to gravity is $g = 9.81\; \rm kg \cdot N^{-1}$ .)

Explanation:

Let $A_1$ denote the first piston's contact area with the fluid. Let $A_2$ denote the second piston's contact area with the fluid.

Similarly, let $F_1$ and $F_2$ denote the size of the force on the two pistons. Since the person is placing all her weight on the first piston:

$F_1 = W = m \cdot g = 50\; \rm kg \times 9.81 \; \rm kg \cdot N^{-1} =495\; \rm N$ .

Since both pistons fit into cylinders, the two contact surfaces must be circles. Keep in mind that the area of a square is equal to $\pi$ times its radius, squared:

$\displaystyle A_1 = \pi \times \left(\frac{1}{2} \times 3.0\right)^2 = 2.25\, \pi\;\rm cm^{2}$ .
$\displaystyle A_2 = \pi \times \left(\frac{1}{2} \times 24\right)^2 = 144\, \pi\;\rm cm^{2}$ .

By Pascal's Law, the pressure on the two pistons should be the same. Pressure is the size of normal force per unit area:

$\displaystyle P = \frac{F}{A}$ .

For the pressures on the two pistons to match:

$\displaystyle \frac{F_1}{A_1} = \frac{F_2}{A_2}$ .

$F_1$ , $A_1$ , and $A_2$ have all been found. The question is asking for $F_2$ . Rearrange this equation to obtain:

$\displaystyle F_2 = \frac{F_1}{A_1} \cdot A_2 = F_1 \cdot \frac{A_2}{A_1}$ .

Evaluate this expression to obtain the value of $F_2$ , which represents the force on the piston with the larger diameter:

$\begin{aligned}F_2 &= F_1 \cdot \frac{A_2}{A_1} \\ &= 495\; \rm N \times \frac{2.25\, \pi\; \rm cm^2}{144\, \pi \; \rm cm^2} \approx 3.1 \times 10^4\; \rm N\end{aligned}$ .

6 0

3 years ago