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2 years ago

How much fuel should you collect before starting a fire?

Physics

1 answer:

juin [17]2 years ago

6 0

Answer:

Collect more fuel than you think you can use; you may need more than you estimate. Pile fine twigs, grass, or bark shavings loosely as a base.

You might be interested in

If evaporation cools the surrounding does condensation warm the surroundings ? explain

kykrilka [37]

Because evaporation requires heat (the latent heat of evaporation) and condensation releases heat (the latent heat of condensation).<span>
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3 0

3 years ago

Read 2 more answers

A population of mammals leaves an ecosystem because of increased temperatures and decreased rainfall. What's the reason for this

DochEvi [55]

Answer:

A. change in abiotic factors

Explanation:

Abiotic factors are those factors that have no life, the most important of which can be mentioned: water, temperature, light, pH, soil, humidity, oxygen and nutrients.

3 0

4 years ago

A current of 32.1 mA flows in a silver wire of diameter 4.57 mm. Find the electric field strength inside the wire. The conductiv

joja [24]

Answer:

$E = \rho J = 3.13\times 10^{-5} ~{\rm N/m}$

Explanation:

The relationship between the current and the electric field inside a wire is given by the following equation:

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

where ρ is the resistivity, and J is the current density. The current density is the current per area:

$J = \frac{I}{A} = \frac{31.2 \times 10^{-3}}{\pi (\frac{4.57 \times 10^{-3}}{2})^2} = 1957$

The resistivity is the reciprocal of conductivity. Therefore,

$\rho = \frac{1}{6.25 \times 10^7} = 1.6 \times 10^{-8}$

Finally, the electric field can be found:

$E = \rho J = 3.13\times 10^{-5} ~{\rm N/m}$

8 0

3 years ago

John throws a rock down with speed 14 m/s from the top of a 30 m tower. If air resistance is negligible, what is the rock's spee

astra-53 [7]

The final velocity of the rock before it touches the ground is 28 m/s.

Answer:

Explanation:

As the rock is thrown down, this means the acceleration due to gravity will be exerting on the rock. So the rock will be exhibiting a free fall motion. Thus, the acceleration of the rock will be equal to the magnitude of acceleration due to gravity. Then using the third equation of motion, we can determine the final velocity of the rock provided the values for initial velocity, displacement and acceleration is given in the problem itself.

So the acceleration is equal to 9.8 m/s² due to its free fall motion and displacement will be equal to the height of the tower which is given as 30 m. And the initial speed of the rock is stated as 14 m/s. The initial speed is represented as u, final speed is represented as v, displacement is represented as s and acceleration is represented as a.

$2as=v^{2}-u^{2}$

Then, 2 × 9.8 × 30 = v²-(14)²

v²=784

v= 28 m/s

So the final velocity of the rock before it touches the ground is 28 m/s.

8 0

4 years ago

Niobium metal becomes a superconductor when cooled below 9K. Itssuperconductivity is destroyed when the surface magnetic fieldex

elena-14-01-66 [18.8K]

Answer:

the maximum current is 500 A

Explanation:

Given the data in the question;

the B field magnitude on the surface of the wire is;

B = μ₀i / 2πr

we are to determine the maximum current so we rearrange to find i

B2πr = μ₀i

i = B2πr / μ₀

given that;

diameter d = 2 mm = 0.002 m

radius = 0.002 / 2 = 0.001 m

B = 0.100 T

we know that permeability; μ₀ = 4π × 10⁻⁷ Tm/A

so we substitute

i = (0.100)(2π×0.001 ) / 4π × 10⁻⁷

i = 500 A

Therefore, the maximum current is 500 A

4 0

3 years ago