<span>Brass is an <u>alloy</u>. An alloy
is a mixture of elements to form a unique material. Brass is a mixture of copper
and zinc and the percentage of each element depends on the desired material. It
has a higher malleability than bronze or zinc. Meaning that it can be bend
easily into it desired form.</span>
Answer:
B. Acidic
Explanation:
Neutral an Basic solutions wouldn't create any reaction
Answer:
The equation of motion is 

Explanation:
Lets calculate
The weight attached to the spring is 24 pounds
Acceleration due to gravity is 
Assume x , is spring stretched length is ,4 inches
Converting the length inches into feet 
The weight (W=mg) is balanced by restoring force ks at equilibrium position
mg=kx
⇒ 
The spring constant , 
= 72
If the mass is displaced from its equilibrium position by an amount x, then the differential equation is



Auxiliary equation is, 

=
Thus , the solution is 

The mass is released from the rest x'(0) = 0
=0


Therefore ,

Since , the mass is released from the rest from 4 inches
inches
feet
feet
Therefore , the equation of motion is 
Explanation:
The two postulates of special theory of relativity
Postulate 1: The law of physics are invariant under any of inertial frame of reference.
Postulate 2: The velocity of light is remains same in each ans every frame of reference and independent of relativity.
They are differ from classical mechanics that in classical mechanics there is no change in mass and length in relative velocity but in relativistic mechanics it changes.
These two postulates implements in phenomenon like time dilation , length contraction etc.
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