Select the correct answer.

A 03-series cylindrical roller bearing with inner ring rotating is required for an application in which the life requirement is

-BARSIC- [3]

Answer:

$\mathbf{C_{10} = 137.611 \ kN}$

Explanation:

From the information given:

Life requirement = 40 kh = 40 $40 \times 10^{3} \ h$

Speed (N) = 520 rev/min

Reliability goal $(R_D)$ = 0.9

Radial load $(F_D)$ = 2600 lbf

To find C10 value by using the formula:

$C_{10}=F_D\times \pmatrix \dfrac{x_D}{x_o +(\theta-x_o) \bigg(In(\dfrac{1}{R_o}) \bigg)^{\dfrac{1}{b}}} \end {pmatrix} ^{^{^{\dfrac{1}{a}}$

where;

$x_D = \text{bearing life in million revolution} \\ \\ x_D = \dfrac{60 \times L_h \times N}{10^6} \\ \\ x_D = \dfrac{60 \times 40 \times 10^3 \times 520}{10^6}\\ \\ x_D = 1248 \text{ million revolutions}$

$\text{The cyclindrical roller bearing (a)}= \dfrac{10}{3}$

The Weibull parameters include:

$x_o = 0.02$

$(\theta - x_o) = 4.439$

$b= 1.483$

∴

Using the above formula:

$C_{10}=1.4\times 2600 \times \pmatrix \dfrac{1248}{0.02+(4.439) \bigg(In(\dfrac{1}{0.9}) \bigg)^{\dfrac{1}{1.483}}} \end {pmatrix} ^{^{^{\dfrac{1}{\dfrac{10}{3}}}$

$C_{10}=3640 \times \pmatrix \dfrac{1248}{0.02+(4.439) \bigg(In(\dfrac{1}{0.9}) \bigg)^{\dfrac{1}{1.483}}} \end {pmatrix} ^{^{^{\dfrac{3}{10}}$

$C_{10} = 3640 \times \bigg[\dfrac{1248}{0.9933481582}\bigg]^{\dfrac{3}{10}}$

$C_{10} = 30962.449 \ lbf$

Recall that:

1 kN = 225 lbf

∴

$C_{10} = \dfrac{30962.449}{225}$

$\mathbf{C_{10} = 137.611 \ kN}$

7 0

2 years ago

In an experiment, one selected two samples of copper-silver alloy. One sample has 40 wt% of silver and 60wt% of copper and the o

mote1985 [20]

I belive it’s 3 sorry if it’s wrong

6 0

3 years ago

A circuit contains a resistor, an inductor, and a capacitor. When an AC voltage is applied across the circuit, the impedance of

katen-ka-za [31]

Answer:

The impedance of the circuit depends on the angular frequency of the voltage source.

Explanation:

In a electric circuit, the magnitude of the impedance, is given by the following expression:

$Z = \sqrt{R^{2} + (Xl-Xc)^{2} (1)$

where R = Resistance

Xl = Inductive reactance = ω*L

Xc = Capacitive Reactance = 1/ωC

and ω = angular frequency of the voltage source.

So, it can be seen that the impedance depends on the value of the constants R,L and C, and on the angular frequency ω.

3 0

2 years ago

Eight energy corporations made plans to increase their combined spending on efficiency programs to $50 million per year for the

tangare [24]

Answer:

F=531831381

Explanation:

There are two ways of doing this question:

1) By Formula

2) By Using Compound interest Table

By Formula:

$F=A*\frac{(1+i)^{n}-1}{i}$

Where:

F is future value

A is annual amount per year

i is interest rate

n is number of years

$F=50 million*\frac{(1+0.08)^{8}-1}{0.08}$

F=531831381

By Using Compound interest Table:

F=A(F/A,i,n)

From Table F/A at i=8% and n=8 is 10.6366

F=50000000*(10.6366)

F=531830000≅531831381

The difference in two answers is due to decimal points if you take value from table to greater decimal points you will get the exact answer as by using formula.

7 0

3 years ago

4. Which type of duct undergoes more rigorous testing before it's labeled?

Alenkasestr [34]

Answer:

Flexible duct

Explanation:

it is flexible duct due to current flow

7 0

2 years ago