Numerade

Questions asked

BEST MATCH

The oxidative-fermentative (OF) test determines if certain Gram-negative rods metabolize glucose aerobically and/or anaerobically. In this test, the bacteria were found to metabolize glucose oxidatively but were not fermentative (red box). What do the OF test results indicate about the growth requirements for this microorganism?

View Answer

BEST MATCH

Indicate whether the pair of structures shown represent stereoisomers, constitutional isomers, different conformations of the same compound, or the same conformation of a compound viewed from a different perspective. Note that cis, trans isomers are an example of stereoisomers.

View Answer

BEST MATCH

A(n) ___________ is a substance that lowers the energy of activation without itself being changed in the reaction. A(n) ___________ is a substance that lowers the energy of activation without itself being changed in the reaction. d) buffer c) aerosol b) catalyst a) emulsion

View Answer

BEST MATCH

1 + $i_L(t)$ L + $v_L(t)$ - $i_C(t)$ 2 CR $v_s$ +

View Answer

BEST MATCH

During sleep Multiple Choice heart rate, respiratory rate, and body temperature decrease; blood pressure increases. heart rate, respiratory rate increase, and blood pressure decrease; body temperature increases. heart rate, respiratory rate, blood pressure, and body temperature all decrease. heart rate and respiratory rate increase; blood pressure and body temperature decrease.

View Answer

BEST MATCH

In the supply and demand graph for money, with quantity of money on the X-axis and the value of money on the Y-axis, the demand curve is O upward sloping. The demand for money increases as the value of money falls. O upward sloping. The demand for money decreases as the value of money falls. O downward sloping. The demand for money increases as the value of money falls. O downward sloping. The demand for money decreases as the value of money falls.

View Answer

BEST MATCH

Static discharge head Oa: 20 mmHg Ob: 40 ft c: 20.12 ft

View Answer

BEST MATCH

3. Two spherical shells (inner radius a and outer radius b) have, between them, a linear dielectric porcelain with relative permittivity $\epsilon_r = 6$. If the inner shell has charge 4Q and the outer shell has charge -2Q: (a) calculate the $\vec{D}$-field everywhere. (b) Then determine the electric field everywhere. (c) Integrate the energy density $u = \frac{1}{2}\epsilon_0 E^2$ over all space to find the total electric potential energy of this system. (5) 4. Consider two co-axial metallic tubes of negligible thickness (inner radius a and outer radius b). The tubes are straight and infinitely long, and between them is a linear dielectric material with electric susceptibility $\chi_e$. (a) If the inner and outer tubes have charge per unit length $\lambda$ and $-\lambda$ spread uniformly over their surfaces, determine the displacement field $\vec{D}$, giving reasons for your steps. (b) Hence find the electric field between the tubes. (c) Determine the capacitance per unit length of the system. (5)

View Answer

BEST MATCH

Question #3 [25 Marks] a) Briefly describe the principle of operation of a transformer. [3 marks] b) Name two types of transformer construction. [2 marks] c) The open-circuit test and the short-circuit test were performed on the primary side of a 20-kVA, 8000/240-V, 60-Hz the transformer, and the following data were taken as shown in Table 1: Page 2 of 3 Open-circuit test (on primary) $V_{oc} = 8000 V$ $I_{oc} = 0.214 A$ $P_{oc} = 400 W$ Short-circuit test (on primary) $V_{sc} = 489 V$ $I_{sc} = 2.5 A$ $P_{sc} = 240 W$ Table 1 i. Calculate the parameters ($R_c$, $X_M$, $R_s$ and $X_s$) of the transformer. [10 marks] ii. Draw the approximate equivalent circuit referred to the primary side. [5 marks] iii. Calculate the efficiency of the transformer, when delivering its full rated output at a power factor of 0.8. [5 marks]

View Answer

BEST MATCH

We consider the nodal polynomial of degree n + 1 defined as w_n+1(t) = Î (t - t_i) i=0 Prove that w_n+(t) = Î£(t - t_i) j=0, jâ‰ i

View Answer

tracy a.