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Anuta_ua [19.1K]

2 years ago

7

A jeweler is determining the optical properties of an unknown blue gemstone. She uses an angle of incidence of 62°, and measures

an angle of refraction of 30°. Assuming the index of refraction of air is 1.0, what is the index of refraction of the gem?

1 answer:

Juliette [100K]2 years ago

3 0

Answer:

n = 1.76

Explanation:

According to the rule of ( n1 sin theta1 = n2 sin theta2 )

we know both angles so we insert them to the law and apply n1 = 1

so 1/2 = n2 sin 62 and we get the final answer

You might be interested in

Calculate the force a 70.0-kg high jumper must exert on the ground to produce an upward acceleration 4.00 times the acceleration

worty [1.4K]

Answer:

3433.5 N

Explanation:

g = Acceleration due to gravity = 9.81 m/s²

m = Mass of person = 70 kg

According to the question

a = Acceleration

$4g=4\times 9.81\\\Rightarrow a=39.24\ m/s^2$

Balancing the forces we have

$F-w=ma\\\Rightarrow F=ma+w\\\Rightarrow F=ma+mg\\\Rightarrow F=m(a+g)\\\Rightarrow F=70(39.24+9.81)\\\Rightarrow F=3433.5\ N$

The required force is 3433.5 N

3 0

1 year ago

An object thrown in the air has a velocity after t seconds that can be described by v(t) = -9.8t + 24 (in meters/second) and a h

marin [14]

Answer and Explanation: Kinetic energy is related to movement: it is the energy an object possesses during the movement. it is calculated as:

$K=\frac{1}{2}mv^{2}$

For the object thrown in the air:

$K=\frac{1}{2}.2.[v(t)]^{2}$

$K=(-9.8t+24)^{2}$

$K=96.04t^{2}-470.4t+576$

Kinetic energy of the object as a function of time: $K=96.04t^{2}-470.4t+576$

Potential energy is the energy an object possesses due to its position in relation to other objects. It is calculated as:

$U=mgh$

For the object thrown in the air:

$U=9.8.2.h(t)$

$U=9.8.2.(-4.9t^{2}+24t+60)$

$U=-96.04t^{2}+470.4t+1176$

Potential energy as function of time: $U=-96.04t^{2}+470.4t+1176$

Total kinetic and potential energy, also known as mechanical energy is

TME = $96.04t^{2}-470.4t+576$ + ( $-96.04t^{2}+470.4t+1176$ )

TME = 1752

The expression shows that total energy of an object thrown in the air is constant and independent of time.

6 0

1 year ago

A closely wound rectangular coil of 80 turns has dimensions 25.0 \rm cm by 40.0 \rm cm. The plane of the coil is rotated from a

Pepsi [2]

Answer:

88.3

Explanation:

Emf in a rotating coil is given by rate of change of flux:

E= dФ/dt=(NABcos∅)/ dt

N: number of turns in the coil= 80

A: area of the coil= 0.25×0.40= 0.1

B: magnetic field strength= 1.1

Ф: angle of rotation= 90- 37= 53

dt= 0.06s

E= (80 × 0.4× 0.25×1.10 × cos53)/0.06= 88.3V

4 0

1 year ago

Read 2 more answers

Una cuerda de violin vibra con una frecuencia fundamental de 435 Hz. Cual sera su frecuencia de vibracion si se le somete a una

EleoNora [17]

Answer:

a) f = 615.2 Hz b) f = 307.6 Hz

Explanation:

The speed in a wave on a string is

v = √ T / μ

also the speed a wave must meet the relationship

v = λ f

Let's use these expressions in our problem, for the initial conditions

v = √ T₀ /μ

√ (T₀/ μ) = λ₀ f₀

now it indicates that the tension is doubled

T = 2T₀

√ (T /μ) = λ f

√( 2To /μ) = λ f

√2 √ T₀ /μ = λ f

we substitute

√2 (λ₀ f₀) = λ f

if we suppose that in both cases the string is in the same fundamental harmonic, this means that the wavelength only depends on the length of the string, which does not change

λ₀ = λ

f = f₀ √2

f = 435 √ 2

f = 615.2 Hz

b) The tension is cut in half

T = T₀ / 2

√ (T₀ / 2muy) = f = λ f

√ (T₀ / μ) 1 /√2 = λ f

fo / √2 = f

f = 435 / √2

f = 307.6 Hz

Traslate

La velocidad en una onda en una cuerda es

v = √ T/μ

ademas la velocidad una onda debe cumplir la relación

v= λ f

Usemos estas expresión en nuestro problema, para las condiciones iniciales

v= √ To/μ

√ ( T₀/μ) = λ₀ f₀

ahora nos indica que la tensión se duplica

T = 2T₀

√ ( T/μ) = λf

√ ) 2T₀/μ = λ f

√ 2 √ T₀/μ = λ f

substituimos

√2 ( λ₀ f₀) = λ f

si suponemos que en los dos caso la cuerda este en el mismo armónico fundamental, esto es que la longitud de onda unicamente depende de la longitud de la cuerda, la cual no cambia

λ₀ = λ

f = f₀ √2

f = 435 √2

f = 615,2 Hz

b) La tension se reduce a la mitad

T = T₀/2

RA ( T₀/2μ) = λ f

Ra(T₀/μ) 1/ra 2 = λ f

fo /√ 2 = f

f = 435/√2

f = 307,6 Hz

5 0

1 year ago

A swimming pool heater has to be able to raise the temperatureof the 40,000 gallons of water in the pool by 10 degress Celsius.H

andrew11 [14]

Answer:b)1770 kWh

Explanation:

Given

volume of water $V=40,000 gallons$

Temperature rise $\Delta T=10^{\circ}C$

$c=4186 J/kg-^{\circ} C$

also 1 kg mass is approximately is 1 gallon

therefore 40,000 gallon is equivalent to 3.8\times 40000 kg

heat Required to raise temperature is

$Q=mc\Delta T$

$Q=3.8\times 40000\times 4186\times 10$

$Q=63,627.2\times 10^5 J$

$Q=63,672.2\times 10^2 KJ$

$Q=1767.42 kWh\approx 1770 kWh$

3 0

1 year ago