If the cross-section of a wire of fixed length is doubled, the resistance of that wire change into doubled.We know that <span>the total </span>length<span> of the wires will </span>affect<span> the amount of </span>resistance. <span> The longer the wire, the more </span>resistance<span> that there will be so the answer is doubled.</span>
<span>a) write a polynomial expression for the position of the particle at any time t greater or equal to zero.
</span>Position is found by integrating velocity:
<span>s(t) = (t^3)/3 - 4t^2 + 7t + c
</span>where c is a constant corresponding to the position at t=0. <span>
b) at what time(s) is the particle changing direction
</span>the particle changes direction whenever the velocity is zero; the velocity function equals
<span>(t-1)(t-7) a difference of squares so the zeros are 1 and 7, it changes direction at 1 second and 7 seconds. </span><span>
c) find the total distance traveled by the particle from t=0 and t=4
</span><span>s(0) = c
s(1) = 8/3 + c
s(4) = 64/3 - 64 + 28 + c.
</span>
from 0 to 1 the particle travels 8/3 units. From 1 to 4 it travels -(64/3 - 36 - 8/3) = (-(56/3 - 108/3))
<span>=-(-52/3) = 52/3 units
</span>
<span>so in total it travels 52/3 + 8/3 =20 units</span>
Answer:
Originally : Level = log I / I0
Currently: Level = 10 log I / I0
Level = 10 log 600 = 10 * 2.78 = 27.8
Note the term 1 bel = 10 decibels
