Questions asked
4. For each of the following multiplication problems, find at least two different ways that a student could use reasoning and/or strategies from pages 200-203 in your textbook, to determine the product. In each case, state the name of the strategies you used and write equations that correspond to those strategies. Be sure to carefully use parentheses to show how the strategy works. a. 6x7 b. 5 x 9
The switch in the circuit shown below has been closed for a long time until $t=0$ when it is opened. What is the circuit time constant $\tau$ for $t>0$? $t=0$ $V_o$ $R_1$ $R_2$ $R_3$ $\tau = [R_1//(R_2+R_3)]C$ $\tau = [R_1+(R_2//R_3)]C$ None of the above $\tau = (R_2//R_3)C$ $\tau = (R_1+R_3)C$ (no answer) Correct Answer: $\tau = (R_1+R_3)C$
Factors that determine the Adequate Intake (AI) of water include age, gender, environment, level of physical activity, and rate of metabolism. Group of answer choices True False
A small, 300 g cart is moving at 1.70 m/s on a frictionless track when it collides with a larger, 5.00 kg cart at rest. After the collision, the small cart recoils at 0.850 m/s.
It is desired to pump ethanol at 20°C through 130 m of straight smooth tubing under laminar-flow conditions, $Re = \rho Vd/\mu$ < 2300. The available pressure drop is 10 kPa. For ethanol at 20°C, $\rho = 789 kg/m^3$ and $\mu = 0.0012 kg/m\cdot s$. What is the maximum possible mass flow in kg/h? The maximum possible mass flow is kg/h.
What are the four periods and paradigms of research oversight? Select the correct answer (s) Group of answer choices Researcher paternalism Regulatory protectionism Equipoise Participant access Community partnership
A company is considering a new equipment purchase from either of 2 suppliers: A) Initial cost $1,500, 5-year useful life, $200 salvage value B) Initial cost $1,600, 5-year useful life, $325 salvage value MARR = 7%
What is the efficiency of a motor that has an output of 0.5 hp and an input of 410 W? Include % as the unit. Answer: Check
Considering the electric field map of the previous problem for two charged lines (in two dimensions), if the electric field in between the charged lines 2.4 cm from the center of the positive-charged line is 42 N/C, what is the electric field 7.8 cm from the center of the positive-charged line? Answer to the nearest N/C.
A <100> oriented silicon wafer 500 µm thick is etched in a KOH solution through a window on the top surface defined by silicon dioxide as shown in the figure. The etch rate normal to (100)-planes is 0.6µm/min. The etch rate ratios are 100:16:1 for the (100):(110):(111)-planes. If the base window ($W_b$) needs to be 10 µm square, what must the dimensions on the top surface be to create this device? (Hint: think of this as an ink jet printer bulk etch problem) $W_t = W_b - 2l \cot 54.7^\circ$ $W_t = W_b - \sqrt{2}l$