Answer:
The charge on the ball bearing 4.507 × 10^-8 C
Explanation:
From Coulomb's law
F = kq1q2/r²
make q2 the subject
q2 = Fr²/kq1
q2 = (1.8×10^-2 × 0.026²) ÷ (9×10^9 × 30×10^-9)
q2 = 4.507 × 10^-8 C
The question is incomplete. The complete question is :
A viscoelastic polymer that can be assumed to obey the Boltzmann superposition principle is subjected to the following deformation cycle. At a time, t = 0, a tensile stress of 20 MPa is applied instantaneously and maintained for 100 s. The stress is then removed at a rate of 0.2 MPa s−1 until the polymer is unloaded. If the creep compliance of the material is given by:
J(t) = Jo (1 - exp (-t/to))
Where,
Jo= 3m^2/ GPA
to= 200s
Determine
a) the strain after 100's (before stress is reversed)
b) the residual strain when stress falls to zero.
Answer:
a)-60GPA
b) 0
Explanation:
Given t= 0,
σ = 20Mpa
Change in σ= 0.2Mpas^-1
For creep compliance material,
J(t) = Jo (1 - exp (-t/to))
J(t) = 3 (1 - exp (-0/100))= 3m^2/Gpa
a) t= 100s
E(t)= ΔσJ (t - Jo)
= 0.2 × 3 ( 100 - 200 )
= 0.6 (-100)
= - 60 GPA
Residual strain, σ= 0
E(t)= Jσ (Jo) ∫t (t - Jo) dt
3 × 0 × 200 ∫t (t - Jo) dt
E(t) = 0
<span>B. It stays the same</span>
Answer:
Explanation:
The power of each of the speakers is 0.535 W. At a distance d intensity of sound can be found by the following formula
Intensity of sound = Power / 4π d²
= .535 / 4 x 3.14 x (27.3/2)²
= 2.286 x 10⁻⁴ J m⁻² s⁻¹
Intensity of sound due to other source = 5.715 x 10⁻⁵J m⁻² s⁻¹
Total intensity = 2 x 2.286 x 10⁻⁴J m⁻² s⁻¹
= 4.57 x 10⁻⁴J m⁻² s⁻¹
b ) In this case, man is standing at distances 18.15 m and 9.15 m from the sources .
The total intensity of sound reaching him is as follows
0.535 / (4 π x18.15² ) + 0.535 / (4 π x9.15² )
= 1.293 x 10⁻⁴ + 5.087 x 10⁻⁴
= 6.38 x 10⁻⁴J m⁻² s⁻¹
Answer:
wavelength.
Explanation:
One complete expression of a waveform beginning at a certain point, progressing through the zero line to the wave’s highest (crest) and lowest (trough) points, and returning to the same value as the starting point is called a is called wavelength. Its can be also defined as the distance between two successive crests or trough points in wave form.
