Answer:
A. Its unique strength allows predetermined engineering stresses to be placed in members to counteract stresses that occur when the unit is subjected to service loads
Explanation:
Prestressed concrete is a structural material that allows for predetermined, engineering stresses to be placed in members to counteract the stresses that occur when they are subject to loading.
It combines the high strength compressive properties of concrete with the high tensile strength of steel.
‘Building Construction Handbook’ (6th ed.), CHUDLEY, R., GREENO, R., Butterworth-Heinemann (2007)
Then the correct answer is:
A. Its unique strength allows predetermined engineering stresses to be placed in members to counteract stresses that occur when the unit is subjected to service loads
Answer:
Answer D. Inertial mass constant, weight decreases.
Explanation:
Khan Academy
Answer: 1.33
Explanation:
We would apply Snell's law which is expressed as
niSinθi = nrSinθr
where
θi = angle of incidence
θr = angle of refraction
ni = index of refraction of the incident medium(air)
nr = index of refraction of the refractive medium(liquid in this case)
From the information given,
ni = 1(index for air)
θi = 37
θr = 27
By substituting these values into the formula, we have
1 * sin37 = nr * sin27
nr = sin37/sin27
nr = 1.33
The index of the liquid is 1.33
Answer
The challenge when trying to protect the environment is expensive clean energy startup cost
Explanation
In attempts to protect the environment, energy users across the globe are shifting to new renewable energy resources which are faced by the challenge of high capital cost. Renewable energy technologies are cheap to operate but very expensive to build. The perception is that renewable energy resources are risky because they require higher construction costs.
The food chain would be disturbed and the ecosystem would not be the same, without the consumers nothing would happen and it would lead to the downfall of the chain.
