Afan blade rotates with angular velocity given by ωz(t)= γ − β t2, where γ = 5.20 rad/s and β = 0.810 rad/s3 . calculate the angular acceleration as a function of time t in terms of β and γ.

Answer : The angular acceleration is

Solution : Given,

The given angular velocity equation is,

At t = 0,    

At t = t,    

Formula used for angular acceleration :

where,

= angular acceleration

= angular velocity at time 't'

= angular velocity at time '0'

t = time

Now put all the given values in this formula, we get the angular acceleration.

Therefore, the angular acceleration is

answer: - 3.) the oxidation state of nitrogen in no changes from +2 to 0, and the oxidation state of carbon in co changes from +2 to +4 as the reaction proceeds.

solution: - as per the rules, oxidation number of oxygen in its compounds is -2. the sum of oxidation numbers of all the elements of a molecule or compound is zero.

also, the oxidation number in elemental form is zero.

in no, the oxidation number of o is -2 so the oxidation number of n is +2 so that the sum is zero.

similarly, the oxidation number of c in co is +2 and o is -2.

on product side the oxidation number of n is 0 as it is in the elemental form() .

oxidation number of c in carbon dioxide is +4 as there are two oxygen in it and we know that each oxygen is -2.

so, oxidation number of n is changing from +2 to 0 and the oxidation number of c is changing from +2 to +4.

since nitrogen is reduced and hence no is acting as an oxidizing agent. carbon is oxidized and so co is acting as a reducing agent.

so, the right choice is number 3.)the oxidation state of nitrogen in no changes from +2 to 0, and the oxidation state of carbon in co changes from +2 to +4 as the reaction proceeds.

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)