All categories

3 years ago

If there are 20 Earthworms in a garden that covers 5 square meters, what is the population density of the earthworms?

Physics

2 answers:

lana66690 [7]3 years ago

7 0

4 earthworms per square meter

hodyreva [135]3 years ago

3 0

I think, I do think.. that it is D.

Wouldn't it be simple to divide 5 from 20, that would equal 4.

4 earthworms per square meter.

You might be interested in

The rhinestones in costume jewelry are glass with index of refraction 1.50. To make them more reflective, they are often coated

Sedaia [141]

Answer:

Explanation:

According to the given question, the computation of minimum coating thickness is shown below:-

The condition for constructive interference is

$2t_{min} = (m + \frac{1}{2} )\times \frac{\lambda}{^nmateral}$

$= (0 + \frac{1}{2} )\times \frac{\lambda}{^nmateral}$

$t = \frac{\lambda}{4n}$

Now we will put the values to the above formula to reach the answer

$= \frac{480nm}{4\times 2.0}$

= 60

Therefore we simply applied the above formula to determine the minimum coating thickness

6 0

3 years ago

A mass MM uniform solid cylinder of radius RR and a mass MM thin uniform spherical shell of radius RR roll without slipping. If

vampirchik [111]

Answer:

vcyl / vsph = 1.05

Explanation:

The kinetic energy of a rolling object can be expressed as the sum of a translational kinetic energy plus a rotational kinetic energy.
The traslational part can be written as follows:

$K_{trans} = \frac{1}{2}* M* v_{cm} ^{2} (1)$

The rotational part can be expressed as follows:

$K_{rot} = \frac{1}{2}* I* \omega ^{2} (2)$

where I = moment of Inertia regarding the axis of rotation.
ω = angular speed of the rotating object.
If the object has a radius R, and it rolls without slipping, there is a fixed relationship between the linear and angular speed, as follows:

$v = \omega * R (3)$

For a solid cylinder, I = M*R²/2 (4)
Replacing (3) and (4) in (2), we get:

$K_{rot} = \frac{1}{2}* \frac{1}{2} M*R^{2} * \frac{v_{cmc} ^{2}}{R^{2}} = \frac{1}{4}* M* v_{cmc}^{2} (5)$

Adding (5) and (1), we get the total kinetic energy for the solid cylinder, as follows:

$K_{cyl} = \frac{1}{2}* M* v_{cmc} ^{2} +\frac{1}{4}* M* v_{cmc}^{2} = \frac{3}{4}* M* v_{cmc} ^{2} (6)$

Repeating the same steps for the spherical shell:

$I_{sph} = \frac{2}{3} * M* R^{2} (7)$

$K_{rot} = \frac{1}{2}* \frac{2}{3} M*R^{2} * \frac{v_{cms} ^{2}}{R^{2}} = \frac{1}{3}* M* v_{cms}^{2} (8)$

$K_{sph} = \frac{1}{2}* M* v_{cms} ^{2} +\frac{1}{3}* M* v_{cms}^{2} = \frac{5}{6}* M* v_{cms} ^{2} (9)$

Since we know that both masses are equal each other, we can simplify (6) and (9), cancelling both masses out.
And since we also know that both objects have the same kinetic energy, this means that (6) are (9) are equal each other.
Rearranging, and taking square roots on both sides, we get:

$\frac{v_{cmc}}{v_{cms}} =\sqrt{\frac{10}{9} } = 1.05 (10)$

This means that the solid cylinder is 5% faster than the spherical shell, which is due to the larger moment of inertia for the shell.

3 0

3 years ago

Two infinite wires 20 cm apart each carry a current of 3 A into the paper. d I I d/2 d/2 At a distance d 2 below their midpoint,

Rzqust [24]

<u>Answer:</u>

<h3>As electric current is carried in a cable, around it, a magnetic field is created. The lines of the magnetic fields form concentric circles around the wire. The direction of the magnetic field hinges on the direction of the current. It can be calculated by pointing the thumb of your right hand in the direction of the moment, using the "right hand law." The position of your curled fingers is in the magnetic field lines. The magnetic field magnitude depends on the sum of current, and the distance from the wire carrying the charge.</h3>

<u></u>

<u>Explanation:</u>

Determine the direction of vector B magnitude B: $B: B=\mu_{0} * 1 /(2 \pi r): r=d / 2 * \sqrt{2}$

$\cos \alpha=1 / 2 \Rightarrow \alpha=450$

Resultant magnitude strength: $B=2 B^{*} \cos \alpha=B=u_{0}^{*} 1 /(2 \pi r)=4.24^{*} 10^{-6} T=4.24 u T$ its direction is pointing to the left.

Note: Refer the image attached below

3 0

3 years ago

The most common units for expressing the density of a substance are the g/cm3.

Luden [163]

True.

Density = mass / volume, Unit = g / cm³.

This is a common unit because of its affiliation with the SI unit and because that also our popular liquid which is water = 1 g/cm³

6 0

3 years ago

Hey guys i need song requests dbl

Andrew [12]

Answer:

Shiloh dynasty, jucie wrld or xxx or twenty one plot

Explanatio

8 0

3 years ago

Read 2 more answers