How fast must the space shuttle go to cover 20,000 meters in 4.0 seconds?

An object is placed in a fluid and then released. Assume that the object either floats to the surface (settling so that the obje

Irina18 [472]

Answer:

A. Always true

Explanation:

This is because, the buoyancy force is always present whenever and object is placed in a fluid. The magnitude of this buoyancy force is always equal to the weight of the fluid displaced by the object according to Archimedes' principle. This principle is true irrespective of whether the object floats or not. When any object is inserted in a fluid, the buoyancy force is always present irrespective of whether it floats or not.

7 0

2 years ago

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The pull of what is weaker when 2 objects are farther apart

9966 [12]

The gravitational pull is weaker.

7 0

3 years ago

You are given a parallel plate capacitor that has plates of area 27 cm^2 which are separated by 0.0100 mm of nylon (dielectric c

deff fn [24]

Answer:

Applied voltage should be 13.5396 kV

Explanation:

The charge stored by a capacitor when subjected to a potential difference 'v' across it's plates is given by

$Q=\frac{K\epsilon _{o} A}{d}V$

Solving for V we get

$V=\frac{Qd}{K\epsilon _{o}A}$

thus to store a charge of 0.11mC we solve for V as follows

Applying values we get

$V=\frac{0.11\times 10^{-3}\times 0.01\times 10^{-3}}{27\times 10^{-4}\times 3.4\times 8.85\times 10^{-12}}$

$\therefore V=13.5396kV$

7 0

3 years ago

An extremely long wire laying parallel to the x -axis and passing through the origin carries a current of 250A running in the po

viktelen [127]

Answer:

$1.232\times 10^{-5}\ T.$

Explanation:

<u>Given:</u>

Current through the wire, passing through the origin, $I_1 = 250\ A.$

Current through the wire, passing through the y axis, $r_y=1.8\ m.$ , $I_2 = 50\ A.$

According to Ampere's circuital law, the line integral of magnetic field over a closed loop, called Amperian loop, is equal to $\mu_o$ times the net current threading the loop.

$\oint \vec B \cdot d\vec l=\mu_o I.$

In case of a circular loop, the directions of magnetic field and the line element $d\vec l$ , both are along the tangent of the loop at that point, therefore, $\vec B\cdot d\vec l = B\ dl$ .

$\oint \vec B \cdot d\vec l = \oint B\ dl = B\oint dl.\\$

$\oint dl$ is the circumference of the Amperian loop = $2\pi r$

Therefore,

$B\ 2\pi r=\mu_o I\\B=\dfrac{\mu_o I}{2\pi r}.$

It is the magnetic field due to a current carrying wire at a distance r from it.

For the first wire, passing through the origin:

Consider an Amperian loop of radius 3.510 m, concentric with the axis of the wire, such that it passes through the point where magnetic field is to be found, therefore, $r_1 = 3.510\ m.$

The magnetic field at the given point due to this wire is given by:

$B_1 = \dfrac{\mu_o I_1}{2\pi r_1}\\=\dfrac{4\pi \times 10^{-7}\times 250}{2\pi \times 3.510}=1.42\times 10^{-5}\ T.$

For the first wire, passing through the y-axis:

Consider an Amperian loop of radius (3.510+1.8) m = 5.310 m, concentric with the axis of the wire, such that it passes through the point where magnetic field is to be found, therefore, $r_2 = 5.310\ m.$

The magnetic field at the given point due to this wire is given by:

$B_2 = \dfrac{\mu_o I_2}{2\pi r_2}\\=\dfrac{4\pi \times 10^{-7}\times 50}{2\pi \times 5.310}=1.88\times 10^{-6}\ T.$

The directions of current in both the wires are opposite therefore, the directions of the magnetic field due to both the wires are also opposite to that of each other.

Thus, the net magnetic field at $r_r=-3.510\ m$ is given by

$B=B_1-B_2 = 1.42\times 10^{-5}-1.88\times 10^{-6}=1.232\times 10^{-5}\ T.$

6 0

2 years ago

A truck is speeding up as it travels on an interstate. The truck's momentum (in kg · m/s) is proportional to the truck's speed (

serious [3.7K]

Answer:

a)48300 times

b)P = 821100 kg · m/s

Explanation:

Given that

m = 48300 kg

v= 23 m/s

We know that linear momentum (P) given as

P = m v

P = 48300 x 23 kg · m/s

So we can say that truck momentum is 48300 times its velocity.

Now given that

v= 17 m/s

P = m v

P = 48300 x 17 kg · m/s

P = 821100 kg · m/s

6 0

3 years ago

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