Answer:
Explanation:
For third normal mode of vibration
l =
, λ is wavelength , l is length of string .
.4 = ![\frac{3\lambda}{2}](https://tex.z-dn.net/?f=%5Cfrac%7B3%5Clambda%7D%7B2%7D)
λ = .267 m
velocity = ![\sqrt{\frac{T}{m} }](https://tex.z-dn.net/?f=%5Csqrt%7B%5Cfrac%7BT%7D%7Bm%7D%20%7D)
T is tension and m is mass unit length
m = .5 x 10⁻³ / 40 x 10⁻²
= .00125 kg / m
Putting the values
velocity = ![\sqrt{\frac{80}{.00125} }](https://tex.z-dn.net/?f=%5Csqrt%7B%5Cfrac%7B80%7D%7B.00125%7D%20%7D)
= 253 m /s
frequency
= velocity / λ
= 253 / .267
= 947.5 Hz .
Answer:
Solids: Sound travels fastest through solids. This is because molecules in a solid medium are much closer together than those in a liquid or gas, allowing sound waves to travel more quickly through it. In fact, sound waves travel over 17 times faster through steel than through air
Explanation:
Answer:
I = 1.06886 N s
Explanation:
The expression for momentum is
I = F t = Δp
therefore the momentum is a vector quantity, for which we define a reference system parallel to the floor
Let's find the components of the initial velocity
sin 28.2 = v_y / v
cos 28.2= vₓ / v
v_y = v sin 282
vₓ = v cos 28.2
v_y = 42.8 sin 28.2 = 20.225 m / s
vₓ = 42.8 cos 28.2 = 37.72 m / s
since the ball is heading to the ground, the vertical velocity is negative and the horizontal velocity is positive, it can also be calculated by making
θ = -28.2
v_y = -20.55 m / s
v_x = 37.72 m / s
X axis
Iₓ = Δpₓ = ![p_{fx} - p_{ox}](https://tex.z-dn.net/?f=p_%7Bfx%7D%20-%20p_%7Box%7D)
since the ball moves in the x-axis without changing the velocity, the change in moment must be zero
Δpₓ = m
- m v₀ₓ = 0
v_{fx} = v₀ₓ
therefore
Iₓ = 0
Y axis
I_y = Δp_y = p_{fy} -p_{oy}
when the ball reaches the floor its vertical speed is downwards and when it leaves the floor its speed has the same modulus but the direction is upwards
v_{fy} = - v_{oy}
Δp_y = 2 m v_{oy}
Δp_y = 2 0.0260 (20.55)
= 1.0686 N s
the total impulse is
I = Iₓ i ^ + I_y j ^
I = 1.06886 j^ N s
1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23 25, 27,29 if we add 3 numbers From this we get the answer 30
Westkost [7]
Answer:
none of these numbers added equal 30
Explanation:
it is impossible to get 30 when you have three odd numbers