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Alexeev081 [22]
3 years ago
14

A flashlight has a resistance of 30 Q and is connected

Physics
1 answer:
Talja [164]3 years ago
7 0

Answer:

3 A

Explanation:

The relationship between voltage, current and resistance in a conductor is expressed by Ohm's law, which states that:

V=RI

where:

V is the potential difference across the conductor

R is the resistance of the conductor

I is the current flowing through it

In this problem, for this flashlight we have:

V = 90 V is the potential difference

R=30 \Omega is the resistance of the flashlight

Solving for I, we find the current:

I=\frac{V}{R}=\frac{90}{30}=3 A

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zhuklara [117]

Answer:

Dance studio

Explanation:

Martial art use to defend ourself from any dangerous. Dance is a way to learn it

3 0
3 years ago
Describe how the number of photoelectrons emitted from a metal plate in the photoelectric effect would change if the following o
andrew-mc [135]

Answer:

a) True. The number of photoelectrons is proportional to the amount (intensity) of the incident beam. From the expression above we see that threshold frequency cannot emit electrons.

b)   λ = c / f

Therefore, as the wavelength increases, the frequency decreases and therefore the energy of the photoelectrons emitted,

c)  threshold energy

        h f =Ф

Explanation:

It's photoelectric effect was fully explained by Einstein by the expression

       Knox = h f - fi

Where K is the kinetic energy of the photoelectrons, f the frequency of the incident radiation and fi the work function of the metal

a) True. The number of photoelectrons is proportional to the amount (intensity) of the incident beam. From the expression above we see that threshold frequency cannot emit electrons.

b) wavelength is related to frequency

         λ = c / f

Therefore, as the wavelength increases, the frequency decreases and therefore the energy of the photoelectrons emitted, so there is a wavelength from which electrons cannot be removed from the metal.

c) As the work increases, more frequency radiation is needed to remove the electrons, because there is a threshold energy

        h f =Ф

7 0
3 years ago
The layer of earth that has the lightest elements is the
Sonja [21]
If I remember correctly (from my studies long time ago) the layers are from the outer to the center:
SiAl : Silicon-Aluminum
SiMa : Silicon-Magnesium (although should be Mg)
NiFe : Nickel-Iron

The SiMa layer should have the lightest elements (Magnesium is lighter than Aluminum)
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4 years ago
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Mkey [24]

An LED is useful because when a current passes through it, it gives out light.

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2 years ago
If an object were released in space far away from planted or stars and given an initial momentum, describe what would happen to
mamaluj [8]
Strange as it may seem, the object would keep moving, in a straight line and at the same speed, until it came near another object. Its momentum and kinetic energy would never change. It might continue like that for a billion years or more.

Have a look at Newton's first law of motion.
7 0
3 years ago
Read 2 more answers
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