To halt the decline in biodiversity, we must do which of the following?

You’ve made the finals of the science Olympics. As one of your tasks you’re given 1.0 g of copper and asked to make a cylindrica

Pani-rosa [81]

Answer:

Length = 2.92 m

Diameter = 0.11 mm

Explanation:

We have $m = dl D \ \ \& \ \ \ R = \frac{\rho l}{A}$ , where:

$l$ is the length

$m = 1.0 g = 1 \times 10^{-3} \ kg\\R = 1.3 \ \Omega\\\rho = 1.7 \times 10^{-8} \Omega m\\d = 8.96 \ g/cm^3 = 8960 kg/m^3$

We divide the first equation by the second equation to get:

$\frac{m}{R} = \frac{d A^2}{\rho}$

$A^2 = \frac{m \rho}{dR} \\\\A^2 = \frac { 1 \times 10^{-3} \times 1.7 \times 10^{-8}}{8960 \times 1.3}\\\\A^2 = 1.5 \times 10^{-15}\\\\ A= 3.8 \times 10^{-8} \ m^2$

Using this Area, we find the diameter of the wire:

$D = \sqrt{\frac{4A}{\pi}}$

$D = \sqrt{\frac{4 \times 3.8 \times 10^{-8} }{\pi}}$

$D = 0.00011 \ m = 1.1 \times 10^ {-4} = 0.11 \ mm$

To find the length, we multiply the two equations stated initially:

$mR = d\rho l^2\\\\l^2 = \frac{mR}{d\rho} \\\l^2 = \frac {1.0 \times 10^{-3} \times 1.3}{8960 \times 1.7\times 10^{-8}}$

$l^2 = 8.534\\l = 2.92 \ m$

8 0

2 years ago

Read 2 more answers

Difference between rest and motion

creativ13 [48]

Rest - it is the state in which body doesn’t move from it’s place

motion - it is the state in which body moves from it’s place

3 0

2 years ago

In a physics lab experiment, a spring clamped to the table shoots a 22g ball horizontally. When the spring is compressed 21cm ,

worty [1.4K]

a square and a triangle I think

6 0

3 years ago

To transform electrical energy into mechanical energy, the electromagnet in a

lidiya [134]

Answer:

Motors commonly contain a "commutator" which allows a magnetic field due to a loop of wire to always be in a say "clockwise or counterclockwise" direction even tho the loop of wire is rotating.

That means that magnetic field due to the surrounding magnets is always in the same direction, but the magnetic field due to the rotating loop of wire is continually changing so that it will always oppose the surrounding field which remains in a constant direction.

This is most easily seen in a "DC - direct current motor".

6 0

1 year ago

A woman pushes an oak chest across an oak floor at a constant speed of 0.450 m/s. The chest has a mass of 40.0 kg, and the coeff

natima [27]

Answer:

A. 243 N

Explanation:

Friction is the force that opposes the relative motion between systems that are in contact.

This friction force that opposes the motion of the oak chest across the oak surface will be equal and opposite to that exerted by the woman.

First find the normal force which is the force that would point directly upwards to support weight of the block.

Normal force, N= mg where m is the mass of the chest and g is the acceleration due to gravity.

Given m=40 kg and g=9.80 m/s²

N force=40×9.80 =392N

Then find the force of friction which is given by the formula;

<em>F=μN where μ is friction coefficient for the oak chest and N is the normal force on the chest</em>

Given <em>μ</em>=0.620 and N force = 392 N then it will be;

F=0.620× 392 =243.04 N

Answer : 243 N

6 0

2 years ago