What property of sound depends on the energy and intensity of the sound wave?

Assuming that Albertine's mass is 60.0 kg , for what value of μk, the coefficient of kinetic friction between the chair and the

makvit [3.9K]

Answer:

$\mu_k=0.101$

Explanation:

It is given that,

Mass of Albertine, m = 60 kg

It can be assumed, the spring constant of the spring, k = 95 N/m

Compression in the spring, x = 5 m

A glass sits 19.8 m from her outstretched foot, h = 19.8 m

When she just reach the glass without knocking it over, a force of friction will also act on it. Using the conservation of energy for the spring mass system such that,

$\dfrac{1}{2}kx^2=\mu_k mgh$

$\mu_k=\dfrac{kx^2}{2mgh}$

$\mu_k=\dfrac{95\times (5)^2}{2\times 60\times 9.8\times 19.8}$

$\mu_k=0.101$

So, the coefficient of kinetic friction between the chair and the waxed floor is 0.101. Hence, this is the required solution.

3 0

3 years ago

A baseball player friend of yours wants to determine his pitching speed. you have him stand on a ledge and throw the ball horizo

zhenek [66]

Answer:

The pitching speed of your friend is 33.20 m/s

Explanation:

Lets explain how to solve the problem

Your friend throw the ball horizontally that means the vertical initial

component of velocity is zero ( $u_{y}=0$ ).

The ball is thrown from a height 4 meters above the ground.

The height $h=u_{y}t+\frac{1}{2}gt^{2}$

Remember: the height is negative value because its below the point of

thrown (initial position)

h = -4 m , $u_{y}=0$ and g = -9.8 m/s²(downward)

Substitute these values in the rule above

⇒ $4=0-\frac{1}{2}(9.8)t^{2}$

⇒ -4 = -4.9t² (multiply both sides by -1)

⇒ 4 = 4.9t² (divide both sides by 4.9)

⇒ 0.81633 = t² (take √ for both sides)

⇒ t = 0.9035

Then the time of the ball to land on the ground is 0.9035 seconds

The range of the ball on the ground is 30 m

The range $R=u_{x}*t$ , where $u_{x}$ is the horizontal

component of the initial velocity

R = 30 meters and t = 0.9035

⇒ $30=u_{x}(0.9035)$ (divide both sides by 0.9035)

⇒ $u_{x}=33.20$ m/s

The pitching speed of your friend is 33.20 m/s 

4 0

3 years ago

During an experiment, you take a measurement of 12.9 inches.

svlad2 [7]

Answer:

1 inch = 2.54 cm

12.9 inches= 12.9 x 2.54

= 32.766

= 32.8 cm (approximately)

Hope it helps...

7 0

3 years ago

Help is requested. Will give brainliest to anyone who answers correctly.

sp2606 [1]

The answer should be d because they are constantly rotating

4 0

4 years ago

A certain kind of glass has an index of refraction of 1.640 for blue light of wavelength 440 nm and an index of 1.595 for red li

seraphim [82]

Answer: 18.27°

Explanation:

Given

Index of refraction of blue light, n(b) = 1.64

Wavelength of blue light, λ(b) = 440 nm

Index of refraction of red light, n(r) = 1.595

Wavelength of red light, λ(r) = 670 nm

Angle of incident, θ = 30°

Angle of refraction of red light is

θ(r) = sin^-1 [(n(a)* sin θ) / n(r)], where n(a) = index of refraction of air = 1

So that,

θ(r) = sin^-1 [(1 * sin 30) / 1.595]

θ(r) = sin^-1 (0.5 / 1.595)

θ(r) = sin^-1 0.3135

θ(r) = 18.27°

4 0

3 years ago