Investigating Inflammable Materials - Assignment Example

Considering a dully-red room that is obtained from figure 1as a faint red glow, the temperature is 4800C.

Converting the obtained temperature in Kelvin;

Then;

Therefore;

Figure 2: Radiant heat fluxes

The maximum radiant heat flux for indefinite skin exposure obtained from figure 2 is 16KN/m2. The thermal radiation from the compartment is 18 times that of the maximum radiant heat flux for indefinite skin exposure. This therefore means that the thermal radiation from the room is very fatal and can cause sudden pain and death to any human near the room.

Question 4

Wavelength is the distance obtained between two wave cycles which are in most cases propagated in a given space. It is measured in metres.

The wavelength equation is given as;

Where;

Given;

Let

Then;

Radio wave is in the category of electromagnetic wave which therefore means that its speed is equivalent to the speed of light which is .

Therefore, Smooth radio 100.4 has a speed of .

The Radio frequency is 100.4 MHz

Therefore;

In calculating the wavelength of light, let

Therefore;

Visible light has the highest frequency hence resulting to the lowest wavelength. This therefore means that the higher the frequency of a wave the lower the wavelength. Since the smooth radio has the lowest frequency of 100.4 MHz, the wavelength obtained is very high (3.785m).

Question 5

Given;

Converting the given temperatures into Kelvin;

Therefore;

Activation energy Ea=100Kj/mole

The Arrhenius equation will be used to solve this problem.

The equation is written as;

Where;

Taking natural logs of equation (i) we obtain;

Rearranging equation (ii) to obtain equation of the straight line;

The resulting equation is;

When a plot of lnk against 1/T is made, then the slope of the plot will be;

Since k and Z are the constants in the equation; equation (i) can be sufficiently used to determine the reaction rate constant. Therefore;

The chemical reaction rate is higher at than at at chemical reaction rates of 0.765M/s and 0.66M/s respectively. This clearly indicates that a higher chemical reaction rate is experienced at a higher temperature. This is because as the temperature increases in a chemical reaction, the reacting molecules moves faster hence collide at a higher frequency since they carry more kinetic. This therefore facilitates the chemical reaction.

Question 6

The mixed fuel has the following concentration;

• methane is 0.55% volume
• carbon monoxide is 0.35% volume
• hydrogen is 0.10 % volume

The Le Chatelier mixing rule is applied in this case;

Where;

Let;

Therefore;

Question 7

The given parameters include;

• diameter of pan=0.80m
• heat release intensity =450KN/m2

The equation used to determine the flame height under normal atmospheric condition;

Where;

Therefore;

Question 8

The given parameters include;

Therefore;

Then;

Distance to the fire exit is as given below;

The time required for the first part of travel;

Assuming that at the fire exit then deceleration but

Therefore;

Question 9

The given parameters include;

Therefore;

Then;

Therefore;

Then;

The possible routes are;

Since the air speed will affect the overall speed of the person, it is important to determine the resultant speed.

Since;

The diagrammatic presentation of the speeds can be visualized as;

Figure 3

The resultant speed acts at an angle of 19.80 degrees to the vertical. Since the angle of the speed has changed, the distance of travel also has to change. Therefore, the distance to be travelled has to be calculated using the following figure.

Figure 4

From figure 4;

Therefore;

Therefore;

Then;

Therefore;

Speed DC is equivalent to the person’s evacuation speed since the air speed in the corridor does not influence the overall speed. This is because; the place is not within the corridor. Therefore;

Total time taken, is obtained as follows;

The minimum time required for the evacuation is 9.736s. This is obtained by considering the fact that the shortest distance is always the hypotenuse.

Question 10

The given parameters include;

Therefore;

Then;

Therefore;

The diagrammatic presentation of the expected speed and direction can be visualized as;

Figure 5

Since the air speed will affect the overall speed of the person, it is important to determine the resultant speed.

Since;

The resultant speed acts at an angle of 19.80 degrees to the vertical. Therefore, the distance to be travelled has to be calculated.

Then;

The possible routes are;

Therefore;

Therefore;

Determining distance BC;

Then;

The route distance;

Speed DC is equivalent to the person’s evacuation speed because; the place is not within the corridor. Therefore;

Total time taken, is obtained as follows;

It can be clearly seen that as the speed of the air changes direction from 0.45m/s to -0.45 m/s, the time taken for the person to evacuate to the fire exit position changes significantly from 9.736s to 15.50s. This is because; the air speed tends to push the person away from the fire exit position. The person is therefore forced to use the longer path in evacuating.