Answer:
is this a question? I am confused
Sound waves can combine to become bigger. true
Answer:
Assume that this wavelength is measured in vacuum. The energy on each photon of this wave would be approximately .
Explanation:
The Planck-Einstein Relation relates the energy of a photon to its frequency :
,
where is Planck's Constant.
.
This question did not provide the frequency of this wave directly; the value of needs to be calculated from the wavelength of this wave. Assume that this wave is travelling at the speed of light in vacuum:
.
The frequency of this electromagnetic wave would be:
.
Apply the Planck-Einstein Relation to find the energy of a photon of this electromagnetic wave:
.
Note that combining the two equations above ( and ) will give:
.
This equation is supposed to give the same result (energy of a photon of this wave given its wavelength and speed) in one step:
.
To find the velocity of the bullet just before reaching the ground, we use the formula.
Vy = Vosen (30 °) + gt (1).
For that we need to know the time it takes for the bullet to reach the ground from the moment it is fired.
For that we use the formula:
Xy = Xo + Vosen (30 °) * t + 0.5gt ^ 2 (2)
where:
Vy = Component of the speed in the y direction (vertical)
Vo = initial velocity of the bullet at the exit of the cannon
g = acceleration of gravity
Xy = vertical component of the position.
Xo = initial position.
t = time.
To find the time it takes for the bullet to reach the ground, we make Xy = 0 and clear t.
then it would be:
0 = 10 + 80sen (30 °) * t +0.5 * (- 9.8) t ^ 2.
The solution to that equation is:
t = 8.4 seconds.
We substitute that time in equation (1) and clear Vy.
We have left:
Vy = 80 * sin (30 °) + 9.8 * (8.4)
Vy = 42.38 m / s
Answer:
The 50N weight be hung at 23 cm to maintain equilibrium
Explanation:
Given;
length of the uniform rod = 30 cm
center of the uniform rod = 15 cm
weight of 40N is hung at 5 cm mark
weight of 50 N will be hung at ?
0------5cm-----------------15cm-------------P---------30cm
↓ 10cm Δ xcm ↓
40N 50N
Take moment about the pivot point and apply the principle of moment
50N (x cm) = 40N (10 cm)
x = (400) / 50
x = 8cm
P = x cm + 15 cm
P = 8 cm + 15 cm
P = 23 cm
Therefore, the 50N weight be hung at 23 cm to maintain equilibrium