Answer:
A sand bed is necessary because it provides a refractory bottom for molten metal
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WHICH TASK BEST FITS THE ROLE OF A DESIGN ENGINEER ?
Answer: drafting blueprints
Explanation:
An asphalt concrete mixture includes 94% aggregate by weight. The specific gravities of aggregate and asphalt are 2.65 and 1.0, respectively. If the bulk density of the mix is 147 pcf, what is the percent voids in the total mix
Answer:
2.0%
Explanation:
Percentage of aggregate = 94%
Specific gravity = 2.65
Specific gravity of asphalt = 1.9
Density of mix = 147pcf = 147lb/ft³
Total weight of mix: (volume = 1ft³)
= (147lb/ft³)(1ft³)
= 147lb
Percentage weight of asphalt in mix:
100% - 94%
= 6%
Weight of asphalt binders
= 6% x 147lb
= 8.82lb
Weight of aggregate in mix:
= 94% x 147
= 138.18lb
Specific weight of asphalt binder:
(Gab)(Yw)
Yw = specific Weight of water
= 62.4lb
Gab = specific gravity of asphalt binder
= 1.0
(62.4lb)(1.0)
= 62.4 lb/ft³
Volume of asphalt in binder:
8.82/62.4
= 0.14ft³
Specific weight of binder in mix:
2.65 x 62.4lb/ft³
= 165.36 lb/ft³
Volume of aggregate:
= 138.18/165.36
= 0.84ft³
Volume of void in the mix:
1ft³ - 0.84ft³ - 0.14ft³
= 0.02ft³
The percentage of void in total mix:
VTM = (0.02ft³/1ft³)100
= 2.0%
It is desirable to model a battery by its Thevenin equivalent. To do this, two precision resistors are used. In particular, a 25 Ohm resistor gives a 20 V drop and a 15 Ohm resistor gives a 15 V drop. The Thevenin's equivalent resistance is most nearly
1. 100 ohms
2. 75 Ohms
3. 25 Ohms
4. 15 Ohms
5. 40 Ohms
Answer:
3. 25 ohms
Explanation:
Already we are aware that
Vth = IRth + VL
RL = 25 ohms
VL = 20v
I = vL/RL
I = (20/25)A
Vth = (20/25)Rth + 20
25Vth = 20Rth + 20x25
= 25Vth - 20Rth + 500 --- (a)
RL = 15 ohms VL = 15v
I = 15/15 = 1A
Vth = 1 x Rth + 15
Vth - Rth = 15 --- (b)
When we solve equations a and b simultaneously,
Vth = 40V, Rth = 25 ohms
Therefore the answer is 25ohms.
Beginning with model year 2008, what type of communication protocol is required for diagnostics?
Beginning with model year 2008, Controller Area Network (CAN) is required for diagnostics.
What is diagnostics?Diagnostics are defined as the process of identifying an injury, ailment, or disease based on the symptoms and signs a person is exhibiting. In order to confirm or rule out illnesses and diseases, diagnostic tests are utilized. Before creating a treatment plan, your doctor needs particular information from a diagnostic test to make an accurate diagnosis.
The robust automotive bus standard known as a Controller Area Network (CAN) enables microcontrollers and other devices to interact with each other's applications without the need for a host computer. Devices and CAN busses are frequently found in industrial and automotive systems. Bosch created the Controller Area Network (CAN) bus, which saw its debut in manufacturing in 1991.
Thus, beginning with model year 2008, Controller Area Network (CAN) is required for diagnostics.
To learn more about diagnostics, refer to the link below:
https://brainly.com/question/12814536
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