Answer:
The amplitude of the eardrum's oscillation is 6.65×10^-13 m.
Explanation:
Given data:
The sound has a frequency of 262 Hz
The sound level is 84 dB
The air density is 1.21 kg/m^3
The speed of sound is 346 m/s
Solution:
As, Intensity of sound is given by,
I = Io×10^(s/10 db)
I = 2×π^2×ρ×v×f^2×Sm^2
Thus,
Sm = √(Io×10^(s/10 db)) / √( 2×π^2×ρ×v×f^2)
Now, put the values,
Sm = √( 10^-12 × 10^(84/10) ) / √( 2×(3.14)^2×1.21×346×(262)^2 )
Sm = √(2.51×10^-4 / 5.66×10^8)
Sm = √0.443×10^-12
Sm = 6.65×10^-13 m.
Answer:
a) p = 4.96 10⁻¹⁹ kg m / s
, b) p = 35 .18 10⁻¹⁹ kg m / s
,
c) p_correst / p_approximate = 7.09
Explanation:
a) The moment is defined in classical mechanics as
p = m v
Let's calculate its value
p = 1.67 10⁻²⁷ 0.99 3. 10⁸
p = 4.96 10⁻¹⁹ kg m / s
b) in special relativity the moment is defined as
p = m v / √(1 –v² / c²)
Let's calculate
p = 1.67 10⁻²⁷ 0.99 10⁸/ √(1- 0.99²)
p = 4.96 10⁻¹⁹ / 0.141
p = 35 .18 10⁻¹⁹ kg m / s
c) the relationship between the two values is
p_correst / p_approximate = 35.18 / 4.96
p_correst / p_approximate = 7.09
Answer:
15,505 N
Explanation:
Using the principle of conservation of energy, the potential energy loss of the student equals the kinetic energy gain of the student
-ΔU = ΔK
-(U₂ - U₁) = K₂ - K₁ where U₁ = initial potential energy = mgh , U₂ = final potential energy = 0, K₁ = initial kinetic energy = 0 and K₂ = final kinetic energy = 1/2mv²
-(0 - mgh) = 1/2mv² - 0
mgh = 1/2mv² where m = mass of student = 70kg, h = height of platform = 1 m, g = acceleration due to gravity = 9.8 m/s² and v = final velocity of student as he hits the ground.
mgh = 1/2mv²
gh = 1/2v²
v² = 2gh
v = √(2gh)
v = √(2 × 9.8 m/s² × 1 m)
v = √(19.6 m²/s²)
v = 4.43 m/s
Upon impact on the ground and stopping, impulse I = Ft = m(v' - v) where F = force, t = time = 0.02 s, m =mass of student = 70 kg, v = initial velocity on impact = 4.43 m/s and v'= final velocity at stopping = 0 m/s
So Ft = m(v' - v)
F = m(v' - v)/t
substituting the values of the variables, we have
F = 70 kg(0 m/s - 4.43 m/s)/0.02 s
= 70 kg(- 4.43 m/s)/0.02 s
= -310.1 kgm/s ÷ 0.02 s
= -15,505 N
So, the force transmitted to her bones is 15,505 N
Answer:
a structural variation in which different atoms of the same element have different numbers of neutrons
Explanation:
An isotope is an atom of an element having the same number of protons but different number of neutrons. Different isotopes are used for different purposes. Example: some are used in medicines , food irradiation, etc.
Carbon has three isotopes C 12, C 13, C 14. All three of them have 6 protons but have different numbers of neutrons.
C 12 is a common element and is abundant in nature
C 13 is less abundant than C 12
C 14 is used for dating fossils . It is radioactive
Two atoms with the same atomic number, but different mass numbers (same number of protons, different number of neutrons), are called isotopes, or isotopic nuclides. Having different numbers of neutrons changes the mass of these atoms, so isotopes have slight variations in their physical and chemical behavior.
