How often does a 16-year-old need a medical evaluation from a doctor?

Heated lithium atoms emit photons of light with an energy of 2.961 × 10−19 J. Calculate the frequency and wavelength of one of t

tatiyna

Answer:

4.5 x 10¹⁴ Hz

666.7 nm

1.8 x 10⁵ J

The color of the emitted light is red

Explanation:

E = energy of photons of light = 2.961 x 10⁻¹⁹ J

f = frequency of the photon

Energy of photons is given as

E = h f

2.961 x 10⁻¹⁹ = (6.63 x 10⁻³⁴) f

f = 4.5 x 10¹⁴ Hz

c = speed of light = 3 x 10⁸ m/s

λ = wavelength of photon

Using the equation

c = f λ

3 x 10⁸ = (4.5 x 10¹⁴) λ

λ = 0.6667 x 10⁻⁶ m

λ = 666.7 x 10⁻⁹ m

λ = 666.7 nm

n = number of photons in 1 mole = 6.023 x 10²³

U = energy of 1 mole of photons

Energy of 1 mole of photons is given as

U = n E

U = (6.023 x 10²³) (2.961 x 10⁻¹⁹)

U = 1.8 x 10⁵ J

The color of the emitted light is red

6 0

3 years ago

When using higher magnification, you need more light. which parts of the microscope can be adjusted to provide more light, and h

valina [46]

Increased lamp voltage is achieved by turning the light intensity dial.

To enlarge the diameter of the hole and let more light through the slide, the iris diaphragm was modified.

Condenser: Position it higher and closer to the slide's bottom to better direct light to the centre of the slide.

<h3>How do you adjust the light level on a microscope?</h3>

Utilize the brightness adjustment knob to change the brightness. Turn the brightness control knob while looking through the eyepieces to make sure there is no glare in the field of view.

Use a daylight balancing filter if your compound microscope has a certain sort of illumination. It typically rests directly on top of the luminator or in a filter holder above the light. This filter is blue.

The daylight balancing filter will correct the colour temperature and produce a higher-quality image if your microscope is lighted by tungsten or halogen (and a better colour image). This blue filter is not necessary if your microscope is an LED.

To learn more about light level on a microscope, visit:

brainly.com/question/14727797

#SPJ4

8 0

1 year ago

A 100-W (watt) light bulb has resistance R=143Ω (ohms) when attached to household current, where voltage varies as V=V0sin(2πft)

Phantasy [73]

Complete Question

A 100-W (watt) light bulb has resistance R=143Ω (ohms) when attached to household current, where voltage varies as V=V0sin(2πft), where V0=110 V, f=60 Hz. The power supplied to the bulb is P=V2R J/s (joules per second) and the total energy expended over a time period [0,T] (in seconds) is $U = \int\limits^T_0 {P(t)} \, dt$

Compute U if the bulb remains on for 5h

Answer:

The value is $U = 7.563 *10^{5} \ J$

Explanation:

From the question we are told that

The power rating of the bulb is $P = 100 \ W$

The resistance is $R = 143 \ \Omega$

The voltage is $V = V_o sin [2 \pi ft]$

The energy expanded is $U = \int\limits^T_0 {P(t)} \, dt$

The voltage $V_o = 110 \ V$

The frequency is $f = 60 \ Hz$

The time considered is $t = 5 \ h = 18000 \ s$

Generally power is mathematically represented as

$P = \frac{V^2}{ R}$

=> $P = \frac{( 110 sin [2 \pi * 60t])^2}{ 144}$

=> $P = \frac{ 110^2 [ sin [120 \pi t])^2}{ 144}$

So

$U = \int\limits^T_0 { \frac{ 110^2* [sin [120 \pi t])^2}{ 144}} \, dt$

=> $U = \frac{110^2}{144} \int\limits^T_0 { ( sin^2 [120 \pi t]} \, dt$

=> $U = \frac{110^2}{144} \int\limits^T_0 { \frac{1 - cos 2 (120\pi t)}{2} } \, dt$

=> $U = \frac{110^2}{144} \int\limits^T_0 { \frac{1 - cos 240 \pi t)}{2} } \, dt$

=> $U = \frac{110^2}{144} [\frac{t}{2} - [\frac{1}{2} * \frac{sin(240 \pi t)}{240 \pi} ] ]\left | T} \atop {0}} \right.$

=> $U = \frac{110^2}{144} [\frac{t}{2} - [\frac{1}{2} * \frac{sin(240 \pi t)}{240 \pi} ] ]\left | 18000} \atop {0}} \right.$

$U = \frac{110^2}{144} [\frac{18000}{2} - [\frac{1}{2} * \frac{sin(240 \pi (18000))}{240 \pi} ] ]$

=> $U = 7.563 *10^{5} \ J$

7 0

3 years ago

Maria feels overwhelmed by everything she needs to do for school by next week. How can she best manage this stress?

FrozenT [24]

Answer: Option (b) is the correct answer.

Explanation:

Stress is a situation in which our mind or body feel the pressure from our surroundings, ideas or thoughts. Stress causes distress in the body and mind of an individual.

For example, Ria has not done her homework and she is worried what punishment might her teacher give her when she get to know this.

When can get relive from stress by talking about our thoughts or worries with an individual. The other person might help us solve our problems or he might suggest us in a better way.

Therefore, we can conclude that Maria best manage this stress by talking to family, friends, and teachers for support.

3 0

3 years ago

Read 2 more answers

A politician running for office tells a crowd at a rally that the only way to keep the food chain safe is to stop allowing the g

olasank [31]

Answer:

B. No. He presented no scientific data to support his claim.

6 0

3 years ago