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2 years ago

2. You should hold your fingers on the power switch when holding a plugged-

Engineering

2 answers:

igor_vitrenko [27]2 years ago

6 0

False unless you are using the tool the power button should be off for caution

levacccp [35]2 years ago

4 0

Secure work with clamps or a vise, freeing both hands to operate the tool. Avoid accidental starting. The worker should not hold a finger on the switch button while carrying a plugged-in tool. Tools should be maintained with care so it is FALSE!!

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Advances in vehicle manufacturing technology have decreased the need for:

Llana [10]

Answer:

D large amounts of labor

Explanation:

7 0

2 years ago

Which of the following is not an example of heat generation? a)- Exothermic chemical reaction in a solid b)- Endothermic Chemica

Sav [38]

Answer:

b) Endothermic Chemical Reactions in a solid

Explanation:

Endothermic reactions consume energy, which will result in a cooler solid when the reaction finishes.

8 0

3 years ago

Suppose that the time (in hours) required to repair a machine is an exponentially distributed random variable with parameter ???

Andrej [43]

We need to define the variables,

So,

$F_x (x) = 1-e^{-\lambda x}\\F_x (x) = 1-e^{-0.5x}$

Therefore, the probability that the repair time is more than 4 horus can be calculate as,

$P(x>4)=1-P(x4)= 1-F_x(4)\\P(x>4) = 1-e^{-0.5*4}\\P(x>4) = 1-0.98\\P(x>4) = 0.018$

The probability that the repair time is more than 4 hours is 0.136

b) The probability that repair time is at least 12 hours given that the repair time is more than 7 hoirs is calculated as,

$P(x\geq 12|x>7)=P(X\geq7+5|x>7)\\P(x\geq12|x>7)=P(X\geq5)\\P(x\geq12|x>7)=1-P(x\leq 5)\\P(x\geq12|x>7)=1-e^{-0.5(2)}$

$P(x\geq 12|x>7)=0.6321$

The probability that repair time is at least 12 hours given that the repair time is more than 7 hours is 0.63

3 0

3 years ago

A composite wall is composed of 20 cm of concrete block with k = 0.5 W/m-K and 5 cm of foam insulation with k = 0.03 W/m-K. The

wariber [46]

Answer:

4.8°C

Explanation:

The rate of heat transfer through the wall is given by:

$q=\frac{Ak}{L}dT$

$\frac{q}{A}=\frac{k}{L}dT$

Assumptions:

1) the system is at equilibrium

2) the heat transfer from foam side to interface and interface to block side is equal. There is no heat retention at any point

3) the external surface of the wall (concrete block side) is large enough that all heat is dissipated and there is no increase in temperature of the air on that side

${k_{fi}= 0.03 W/m.K$