Answer:
The light moves through glass, then air
Answer;
- No, Two vectors of unequal magnitude can never sum to zero.
Explanation;
-Two vectors of equal magnitude that are pointing in opposite directions will sum to zero.
-Two vectors of unequal magnitude can never sum to zero. If they point along the same line, since their magnitudes are different, the sum will not be zero.
- If they point in different directions, then you can always decompose one vector into two components: one along the other vector and one perpendicular to the other vector. In this case, the perpendicular component can never be eliminated.
Answer:
Explanation:
When two objects are in thermal equilibrium they are said to have the same temperature. During the process of reaching thermal equilibrium, heat, which is a form of energy, is transferred between the object
which means that it refers to transfer through a selectively permeable partition, the contact path.[1] For the relation of thermal equilibrium, the contact path is permeable only to heat; it does not permit the passage of matter or work; it is called a diathermal connection. According to Lieb and Yngvason, the essential meaning of the relation of thermal equilibrium includes that it is reflexive and symmetric. It is not included in the essential meaning whether it is or is not transitive. After discussing the semantics of the definition, they postulate a substantial physical axiom, that they call the "zeroth law of thermodynamics", that thermal equilibrium is a transitive relation. They comment that the equivalence classes of systems so established are called isotherms
plz dont be mad that i coppied it sounded so good so i wanted veryone to see it when they look bc i am dumb
Answer:
From -15⁰ to 0⁰
H=mc¶
where H= heat absorbed or evolved
m=mass involved
c=specific heat capacity
¶=change in temperature
H=mc¶
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
