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4 years ago

One kilowatt-hour is equal to the energy consumed by an electric device of 1 W for 1 hour true or false

Physics

2 answers:

alexandr1967 [171]4 years ago

7 0

Answer:

That statement is mathematically<em> false.</em>

Explanation:

One kilowatt-hour is equal to the energy consumed by an electric device of <u>1,000 W</u> for 1 hour .

mojhsa [17]4 years ago

6 0

Answer:

False

Explanation:

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Which process do single-celled organisms go through to reproduce asexually?

andrezito [222]

The answer is A-Mitosis

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3 years ago

A gas expands at a constant pressure of 3 atm from a volume of 0.02 cubic meters to 0.10 cubic meters. In the process it experie

Nonamiya [84]

a) $2.4\cdot 10^4 J$

For a gas transformation occuring at a constant pressure, the work done by the gas is given by

$W=p(V_f -V_i)$

where

p is the gas pressure

V_f is the final volume of the gas

V_i is the initial volume

For the gas in the problem,

$p=3 atm = 3\cdot 1.013\cdot 10^5 Pa = 3.039\cdot 10^5 Pa$ is the pressure

$V_i = 0.02 m^2$ is the initial volume

$V_f = 0.10 m^3$ is the final volume

Substituting,

$W=(3.039\cdot 10^5 Pa)(0.10 m^3-0.02m^2)=24312 J = 2.4\cdot 10^4 J$

b) $3.24\cdot 10^5 J$

The heat absorbed by the gas can be found by using the 1st law of thermodynamics:

$\Delta U = Q-W$

where

$\Delta U$ is the change in internal energy of the gas

Q is the heat absorbed

W is the work done

Here we have

$\Delta U = 3.0\cdot 10^5 J$

$W=2.4\cdot 10^4 J$

So we can solve the equation to find Q:

$Q=\Delta U + W = 3.0\cdot 10^5 J +2.4\cdot 10^4 J = 3.24\cdot 10^5 J$

And this process is an isobaric process (=at constant pressure).

8 0

3 years ago

. What is a normal force? It acts against an object slowing it down. It acts perpendicular to an object. It acts with an object

Georgia [21]

Answer:

Explanation:

This is basically asking you what the definition of Normal force is. Normal force is the force that pushes back against the weight of something that is sitting (or standing or lying) perpendicular to it. That's why, when you stand on a floor you don't crash through the floor OR go shooting up into space. The Normal force is equal but opposite to your weight. The floor exerts the normal force (pushing up and is positive) while your weight is opposing it (pushing down and is negative.) Perpendicular is the key word here, I believe.

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3 years ago

Explain why astronomers long ago believed that space must be filled with some kind of substance (the “aether”) instead of the va

professor190 [17]

Answer:Explained

Explanation:

The scientist of that time could not believe that the electromagnetic waves do not require a medium to travel through so they made a space filling substance necessary to travel of electromagnetic waves called aether.

But after the special 0 theory of relativity this idea is discarded and fell out.

6 0

3 years ago

2. A can filled with sand has a mass of 0.65kg is swung overhead in a horizontal circle of radius 0.70m at a constant rate of 2.

Aliun [14]

<h3><u>Answer</u>;</h3>

≈ 5 Kgm²/sec

<h3><u>Explanation</u>;</h3>

Angular momentum is given by the formula

L = Iω, where I is the moment of inertia and ω is the angular speed.

I = mr², where m is the mass and r is the radius

= 0.65 × 0.7²

= 0.3185

Angular speed, ω = v/r

= (2 × 3.142 × r × 2.5) r

= 15.71

Therefore;

Angular momentum = Iω

= 0.3185 × 15.71

= 5.003635

<u>≈ 5 Kgm²/sec</u>

6 0

3 years ago