Answer:
2270 full wavelengths.
Explanation:
The wavelength of the sound wave (assuming sound speed of ) is
.
Now, assuming the distance to the last row is 1947m, the number of wavelengths that fit into this distance are
which is 2270 full wavelengths.
Hence, there are 2270 full wavelengths between the stage and the last row of the crowd.
Answer:
A) ΔV = 1.237 V
B) K.E = 1.237 eV
Explanation:
B)
The initial kinetic energy of the electron is given by the following formula:
where,
K.E = Kinetic Energy of electron = ?
m = mass of elctron = 9.1 x 10⁻³¹ kg
v = speed of electron = 660000 m/s
Therefore,
K.E = 1.98 x 10⁻¹⁹ J
K.E = (1.98 x 10⁻¹⁹ J)()
<u>K.E = 1.237 eV</u>
A)
The energy applied by the potential difference must be equal to the kinetic energy of the electron, in order to stop it:
where,
e = charge on electron = 1.6 x 10⁻¹⁹ C
Therefore,
<u>ΔV = 1.237 V</u>
Answer:
x =4.5 10⁴ m
Explanation:
To find the distance that the particle moves we must use the equations of motion in one dimension and to find the acceleration of the particle we will use Newton's second law
m = 2.00 mg (1 g / 1000 ug) (1 Kg / 1000g) = 2.00 10-6 Kg
q = -200 nc (1C / 10 9 nC) = -200 10-9 C
Let's calculate the acceleration
F = ma
F = q E
a = qE / m
a = -200 10⁻⁹ 1000 / 2.00 10⁻⁶
a = 1 10² m / s²
Let's use kinematics to find the distance traveled before stopping, where it has zero speed (Vf = 0)
Vf² = Vo² -2 a x
0 = Vo² - 2 a x
x = Vo² / 2a
x = 3000²/ 2100
x =4.5 10⁴ m
This is the distance the particule stop, after this distance in the field accelerates in the opposite direction of the initial
Second part
In this case Newton's second law is applied on the y axis
F -W = 0
F = w = mg
E q = mg
E = mg / q
E = 2.00 10⁻⁶ 9.8 / 200 10⁻⁹
E = 9.8 10⁵ C
The direction of the field is such that the force on the particle is up, as the particle has a negative charge, the field must be directed downwards F = qE = (-q) E
Answer:
3500 joules
Explanation:
Multiply the value by 1000.