What W is the amount of force with which gravity is pulling down on something<br>

A sound wave of the form s = sm cos(kx - ?t + f) travels at 343 m/s through air in a long horizontal tube. At one instant, air m

Naddik [55]

Answer:

960.24 Hz

Explanation:

Here is the complete question

A sound wave of the form

S=Smcos(kx−ωt+Φ)

travels at 343 m/s through air in a long horizontal tube. At one instant, air molecule A at x = 2.000 m is at its maximum positive displacement of 6.00 nm and air molecule B at x = 2.070 m is at a positive displacement of 2.00 nm. All the molecules between A and B are at intermediate displacements. What is the frequency of the wave?

Solution

Given x₁ = 2.0 m, x₂ = 2.070 m, maximum positive displacement s = 6.00 nm at x₁, positive displacement s = 2.00 nm at x₂, velocity of wave v = 343 m/s, maximum positive displacement s₀ = 6.00 nm

Let t₀ = 0 at x₁ = 2.0 m for maximum displacement.

So, s = s₀cos(kx−ωt+Φ)

6 = 6cos(2k - 0 + Φ) = 6cos(2k + Φ)⇒ cos(2k + Φ) = 6/6 = 1

cos(2k + Φ) = 1 ⇒ (2k + Φ) = cos⁻¹ (1) = 0 ⇒ 2k + Φ = 0

Let t₀ = 0 at x₂ = 2.070 m for displacement s = 2.00 nm.

So, s = s₀cos(kx−ωt+Φ)

2 = 6cos(2.070k - 0 + Φ) = 6cos(2.070k + Φ)⇒ cos(2.070k + Φ) = 2/6 = 1/3

cos(2.070k + Φ) = 1/3 ⇒ (2.070k + Φ) = cos⁻¹ (1/3) = 70.53 ⇒ 2.070k + Φ = 70.53.

We now have two simultaneous equations.

2k + Φ = 0 (1)

2.070k + Φ = 70.53. (2)

Subtracting (2) -(1)

2.070k - 2k = 70.53

0.070k = 70.53

k = 70.53/0.070 = 1007.554π/180 rad/m = 17.59 rad/m

k = 2π/λ ⇒ λ = 2π/k

and frequency, f = v/λ = v/2π/k = kv/2π = 17.59 × 343/2π = 960.24 Hz

4 0

3 years ago

43. A rocket sled accelerates at a rate of 49.0m/s2. Its passenger has a mass of 75.0 kg. (a) Calculate the horizontal component

lord [1]

(a) 3675 N

Assuming that the acceleration of the rocket is in the horizontal direction, we can use Newton's second law to solve this part:

$F_x = m a_x$

where

$F_x$ is the horizontal component of the force

m is the mass of the passenger

$a_x$ is the horizontal component of the acceleration

Here we have

m = 75.0 kg

$a_x = 49.0 m/s^2$

Substituting,

$F_x=(75.0)(49.0)=3675 N$

(b) 3748 N, 11.3 degrees above horizontal

In this part, we also have to take into account the forces acting along the vertical direction. In fact, the seat exerts a reaction force (R) which is equal in magnitude and opposite in direction to the weight of the passenger:

$R=mg=(75.0)(9.8)=735 N$

where we used

$g=9.8 m/s^2$ as acceleration of gravity.

So, this is the vertical component of the force exerted by the seat on the passenger:

$F_y = 735 N$

and therefore the magnitude of the net force is

$F=\sqrt{F_x^2+F_y^2}=\sqrt{3675^2+735^2}=3748 N$

And the direction is given by

$\theta = tan^{-1}(\frac{F_y}{F_x})=tan^{-1}(\frac{735}{3675})=11.3^{\circ}$

4 0

3 years ago

What is the difference between the parts of the plot with positive slope and the parts with negative slope?

zalisa [80]

The difference between the parts of the plot with positive slope and the parts with negative slope can be found below.

<h3>What is a slope?</h3>

A slope in a graph is the ratio of the vertical and horizontal distances between two points on a line. Slope shows both steepness and direction of values.

A slope can either be positive or negative depending on the relationship between the variables being plotted.

A positive slope means that the variable are directly related while the negative slope means that two variables are negatively related.

A positive slope further means that the line moves upward when going from left to right on the graph while with the negative slope, the line moves down when going from left to right.

Learn more about slope at: brainly.com/question/2491620

#SPJ1

8 0

2 years ago

The process by which pieces of rock are carried away is called:____________

Mama L [17]

Erosion is the process by which pieces of rock are carried away. They are deposited or dropped off somewhere else due to wind, water and other things.

7 0

3 years ago

Una bicicleta que circula a 18km/h y se detiene en 0.8 segundos. Calcular la aceleración.

andrezito [222]

The acceleration is $-6.25 m/s^2$ .