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2 years ago

Explain why solar energy is considered an inexhaustible source of energy

1 answer:

6 0

-- The amount of energy radiated by the sun is not affected at all by how much
of it we use or don't use.

-- The sun is not expected to quit shining on us, or to change its rate of energy
output, at any time within the next several many human lifetimes.

Solar energy is going to keep arriving here, continuously, at the same rate,
free of charge, for a long long time, whether we feel like using it or not. It's
the closest thing to manna from heaven that has been seen around here for
thousands of years.

You might be interested in

Compare the frequency, wavelength, and radiant energy of yellow visible light to that of purple visible light.

dybincka [34]

Answer:

Violet has a higher frequency (approximately 7.5×1014 Hz 7.5 × 10 14 Hz ) than red light (approximately 4.3×1014 Hz 4.3 × 10 14 Hz ). Since the speed of both waves is the same, we infer that violet has a shorter wavelength (400 nm ) than red (700 nm ).

Explanation:

hope it helps this took a lot of my time please mark brainlets!

4 0

1 year ago

Find the velociity of a car which travels 35 m to the right over a period of 40 seconds

GalinKa [24]

Answer:

the velocity of the car is 0.875 m/s

Explanation:

$v = d \div t \\ v = 35m \div 40sec = 0.875 \: m \: per \: sec$

therefore the V of car is 0.875 m

8 0

3 years ago

A 1300-N crate rests on the floor. How much work is required to move it at constant speed (a)

kherson [118]

a) The work done is 920 J

b) The work done is 5200 J

Explanation:

In this first part of the problem, the crate is moved horizontally at constant speed.

The work required in this case is given by

$W=Fd cos \theta$

where

F is the magnitude of the force applied

d is the displacement of the crate

$\theta$ is the angle between the direction of the force and of the displacement

Here the crate is moved at constant speed: this means that the acceleration of the crate is zero, and so according to Newton's second law, the net force on the crate is zero: this means that the force applied, F, must be equal to the force of friction (but in opposite direction), so

F = 230 N

The displacement is

d = 4.0 m

And the angle is $\theta=0^{\circ}$ , since the force is applied horizontally. Therefore, the work done is

$W=(230)(4.0)(cos 0^{\circ})=920 J$

In this case, the crate is moved vertically. The force that must be applied to lift the crate must be equal to the weight of the crate (in order to move it a constant speed), therefore

F = W = 1300 N

The displacement this time is again

d = 4.0 m

And the angle is $\theta=0^{\circ}$ , since the force is applied vertically, and the crate is moved also vertically. Therefore, the work done on the crate this time is

$W=(1300)(4.0)(cos 0^{\circ})=5200 J$

Learn more about work:

brainly.com/question/6763771

brainly.com/question/6443626

#LearnwithBrainly

4 0

3 years ago

If the emf produced in a wire is 0.88 volts and the wire moves perpendicular to a magnetic field of strength 0.075 newtons/amper

Elza [17]

Emf = d (phi-B) / dt
B dA/dt, where dA/dt is the area swept out by the wire per unit time. 
0.88 V = (0.075 N/(A m)) (L)(4.20 m/s), so 
L = (0.88 J/C) / [ (0.075 N s/C m)(4.2 m/s) ] = about 3 meters

6 0

2 years ago

Read 2 more answers

A year 11 pupil with a mass of 55kg swinging back on their chair and falling off it at a speed of 0.6m/s. What is his kinetic en

posledela

Answer:

Uk = 9.9 J

Explanation:

To calculate the kinetic energie (Uk), you can make use of this formula:

Uk = 0.5 * m * v²

given m = 55 kg and v = 0.6 m/s

Substituting in the formula gives:

Uk = 0.5 * 55 * (0.6)²

Uk = 0.5 * 55 * 0.36

Uk = 9.9 J

Extra:

Now let's examine the formula in relation to the SI units. If you understand the following, it will give you great insight in how smart Phisics is inter twained by looking at formulas and their standard units. It will save you time in future to convert formulas, if you use the right standard units.

The formula for kinetic energie is:

Uk = 0.5 * m * v²

Standard SI unit for mass m is kg.

Standard SI unit for speed v is m/s.

So v * v = v² and therefore v² must have the standard SI unit of m²/s².

From the formula, you see that the unit of Uk must be kg*m²/s² and since Uk is normally given in J, these both forms must be the same !

The main unit for Uk is the Joule. Now please see the picture, which shows the relation between the J and other SI units. Please understand that you can construct your 'own' formulas based these units. Now here is the time saver:

Because almost always the right units are given in a question, or because sometimes you can look up a constant in a table with an exotic and seemingly complicated unit, but that says a lot about the formula which must have been some how involved!

By this, I hope you now understand the implication of using the right standard SI units and how that can help you figure out what formula is needed.

3 0

3 years ago