Answer:
a) I = 3.63 W / m²
, b) I = 0.750 W / m²
Explanation:
The intensity of a sound wave is given by the relation
I = P / A = ½ ρ v (2π f
)²
I = (½ ρ v 4π² s_{max}²) f²
a) with the initial condition let's call the intensity Io
cte = (½ ρ v 4π² s_{max}²)
I₀ = cte s² f₀²
I₀ = cte 10 6
If frequency is increase f = 2.20 10³ Hz
I = constant (2.20 10³) 2
I = cte 4.84 10⁶
let's find the relationship of the two quantities
I / Io = 4.84
I = 4.84 Io
I = 4.84 0.750
I = 3.63 W / m²
b) in this case the frequency is reduced to f = 0.250 10³ Hz and the displacement s = 4 s or
I = cte (f s)²
I = constant (0.250 10³ 4)²
I = cte 1 10⁶
the relationship
I / Io = 1
I = Io
I = 0.750 W / m²
The desire for positive reinforcement.
Answer:
![F_x = -\frac{6 C_6}{2^7}](https://tex.z-dn.net/?f=F_x%20%3D%20-%5Cfrac%7B6%20C_6%7D%7B2%5E7%7D)
Attractive
Explanation:
Data provided in the question
The potential energy of a pair of hydrogen atoms given by ![\frac{C_6}{X_6}](https://tex.z-dn.net/?f=%5Cfrac%7BC_6%7D%7BX_6%7D)
Based on the given information, the force that one atom exerts on the other is
Potential energy μ = ![\frac{C_6}{X_6}](https://tex.z-dn.net/?f=%5Cfrac%7BC_6%7D%7BX_6%7D)
Force exerted by one atom upon another
![F_x = \frac{\partial U}{\partial X} = \frac{\partial}{\partial X} (-\frac{C_6}{X^6})](https://tex.z-dn.net/?f=F_x%20%3D%20%5Cfrac%7B%5Cpartial%20U%7D%7B%5Cpartial%20X%7D%20%3D%20%5Cfrac%7B%5Cpartial%7D%7B%5Cpartial%20X%7D%20%20%28-%5Cfrac%7BC_6%7D%7BX%5E6%7D%29)
or
![F_x = \frac{\partial}{\partial X} (\frac{C_6}{X^6})](https://tex.z-dn.net/?f=F_x%20%3D%20%5Cfrac%7B%5Cpartial%7D%7B%5Cpartial%20X%7D%20%20%28%5Cfrac%7BC_6%7D%7BX%5E6%7D%29)
or
![F_x = -\frac{6 C_6}{2^7}](https://tex.z-dn.net/?f=F_x%20%3D%20-%5Cfrac%7B6%20C_6%7D%7B2%5E7%7D)
As we can see that the
comes in positive and constant which represents that the force is negative that means the force is attractive in nature
Answer:
A. Two tennis balls that are near each other
Explanation:
The formula for gravitational force (F) between two objects is
![F = \dfrac{Gm_{1}m_{2}}{d^{2} }](https://tex.z-dn.net/?f=F%20%3D%20%5Cdfrac%7BGm_%7B1%7Dm_%7B2%7D%7D%7Bd%5E%7B2%7D%20%7D)
where m₁ and m₂ are the masses of the two objects, d is the distance between their centres, and G is the gravitational constant.
Thus, two objects that are far from each other will have a smaller gravitational force. We can eliminate Options C and D.
If the objects are at the same distance, those with the smaller mass will have a smaller force.
The mass of a tennis ball is 57 g.
The mass of a soccer ball is 430 g.
Two tennis balls that are near each other will have a smaller gravitational attraction.
The width of the playroom is 4 m