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1 day ago

A wire has an electric field of 6.2 V/m and carries a current density of 2.4 x 108 A/m2. What is its resistivity

Physics

1 answer:

Softa [2.9K]1 day ago

5 0

Response:

The resistivity can be expressed as $\rho = 2.5 *10^{-8} \ \Omega \cdot m$

Clarification:

According to the information provided,

The value of the electric field measures $E = 6.2 V/m$

The density of current is given as $J = 2.4 *10^{8} \ A/m^2$

Typically, resistivity is represented in mathematical terms as

$\rho = \frac{E}{J}$

by inserting values

$\rho = \frac{6.2}{2.4 *10^{8}}$

$\rho = 2.5 *10^{-8} \ \Omega \cdot m$

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Answer:

(A) The tension's magnitude grows to four times the initial value, 4F.

Explanation:

When an object travels in a circular path, a centripetal force is exerted upon it. In this instance, the centripetal force acting on the stone can be represented by $\frac { m{ v }^{ 2 } }{ r }$ .

Here, m denotes the mass of the object

v is the velocity or speed of the object

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Importantly, the tension corresponds to the centripetal force.

Initially, the string completes one revolution each second, and subsequently, it accelerates to perform two revolutions in the same time frame. This signifies that the speed has increased twofold.

Applying our formula:F = $\frac { m{ v }^{ 2 } }{ r }$

where F indicates the tension in the string

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Maintaining the circle's radius, we arrive at:

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From this equation, it's clear that the initial tension has quadrupled.

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12 days ago

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Answer:

1/7 kg

Explanation:

Refer to the attached diagram for enhanced clarity regarding the question.

One of the blocks weighs 1.0 kg and accelerates downward at 3/4g.

g denotes the acceleration due to gravity.

Let M represent the block with known mass, while 'm' signifies the mass of the other block and 'a' refers to the acceleration of body M.

Given M = 1.0 kg and a = 3/4g.

By applying Newton's second law; $\sum fy = ma_y$

For the body with mass m;

T - mg = ma... (1)

For the body with mass M;

Mg - T = Ma... (2)

Combining equations 1 and 2 gives;

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Ma-Mg = -mg-ma

M(a-g) = -m(a+g)

Substituting M = 1.0 kg and a = 3/4g into this equation leads to;

3/4 g-g = -m(3/4 g+g)

3/4 g-g = -m(7/4 g)

-g/4 = -m(7/4 g)

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m = 1/7 kg

Hence, the mass of the other box is 1/7 kg

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1 month ago

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22 days ago

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