There are a few things you need to do in order to become an astronaut.
First, you need to have a bachelor's degree in a STEM field, such as engineering, physics, or mathematics. You should also have a strong understanding of the physical sciences and math.
Next, you need to have at least 1,000 hours of pilot experience. This can be in either a civilian or military aircraft.
You also need to be in excellent physical condition. This includes being able to pass a rigorous physical exam and meet the height and weight requirements.
In addition, you need to be able to speak and understand English fluently.
Once you have met all of the above requirements, you can apply to the NASA astronaut training program. The program is highly competitive, and only a small number of applicants are accepted each year.
The astronaut training program lasts for two years and includes both classroom instruction and hands-on training. During the program, you will learn about space flight, spacecraft systems, and how to live and work in space.
If you successfully complete the astronaut training program, you will be assigned to a mission. You will then spend several years training for your mission.
Once you are ready for your mission, you will launch into space aboard a spacecraft. You will spend several days or weeks in space, conducting experiments and performing maintenance on the spacecraft.
After your mission, you will return to Earth and continue your work with NASA. You may also be asked to speak to the public about your experience as an astronaut.
Becoming an astronaut is a challenging but rewarding career. It is a chance to explore space and to make a difference in the world.
what are the properties of resistors?
There are four main properties of resistors: resistance, resistivity, conductance, and conductivity.
Resistance is the measure of the opposition to current flow in an electrical circuit. It is expressed in ohms (Ω). The resistance of a resistor is determined by its length, cross-sectional area, and resistivity.
Resistivity is the measure of the intrinsic resistance of a material to the flow of electrical current. It is expressed in ohms per meter (Ω·m). The resistivity of a material is determined by its atomic structure and composition.
Conductance is the measure of the ability of a material to conduct electrical current. It is expressed in siemens (S). The conductance of a material is the reciprocal of its resistance.
Conductivity is the measure of the ability of a material to conduct electrical current per unit area. It is expressed in siemens per meter (S/m). The conductivity of a material is the reciprocal of its resistivity.
The following table summarizes the four properties of resistors:
| Property | Symbol | Unit | Formula | |---|---|---|---| | Resistance | R | Ω | $\frac{V}{I}$ | | Resistivity | ρ | Ω·m | $\frac{RA}{l}$ | | Conductance | G | S | $\frac{1}{R}$ | | Conductivity | σ | S/m | $\frac{1}{\rho}$ |
where:
Resistors are used in a variety of electrical circuits to control the flow of current. They can be used to:
Resistors are essential components in any electrical circuit. They are used in everything from simple electronic devices like flashlights and radios to complex machines like computers and automobiles.
what’s the difference between the following voltages electromotive force , Voltage drop , potential difference and terminal voltage
Electromotive force (emf) is the energy per unit charge that is imparted to the charges as they move through a circuit. It is measured in volts (V).
Voltage drop is the difference in electric potential between two points in a circuit. It is measured in volts (V).
Potential difference is the same as voltage drop. It is the difference in electric potential between two points in a circuit. It is measured in volts (V).
Terminal voltage is the voltage measured across the terminals of a battery or other power source. It is equal to the emf of the source minus the voltage drop across the internal resistance of the source. It is measured in volts (V).
Here is a table summarizing the differences between these four terms:
| Term | Definition | Unit | |---|---|---| | Electromotive force (emf) | The energy per unit charge that is imparted to the charges as they move through a circuit | Volts (V) | | Voltage drop | The difference in electric potential between two points in a circuit | Volts (V) | | Potential difference | The same as voltage drop | Volts (V) | | Terminal voltage | The voltage measured across the terminals of a battery or other power source | Volts (V) |
Here's an explanation of the differences between electromotive force, voltage drop, potential difference, and terminal voltage: 1. Electromotive Force (EMF): - EMF is the voltage generated by a source of electrical potential difference, such as a battery or a generator. - It is the force that causes electrons to flow through a circuit. - EMF is measured in volts (V) and is represented by the symbol ε (epsilon). 2. Voltage Drop: - Voltage drop is the decrease in voltage across a component or a section of a circuit due to the resistance of that component or section. - It occurs when current flows through a resistive element, causing a dissipation of energy in the form of heat. - The voltage drop across a component is equal to the product of the current flowing through it and its resistance (Ohm's law: V = IR). 3. Potential Difference: - Potential difference, also known as voltage, is the difference in electric potential energy per unit charge between two points in an electrical circuit. - It is the force that drives electric current through a conductor. - Potential difference is measured in volts (V) and is represented by the symbol V or ΔV. - In a closed circuit, the sum of all potential differences around the circuit is equal to the EMF of the source. 4. Terminal Voltage: - Terminal voltage is the voltage measured across the terminals of a source or a load in a circuit. - It is the potential difference between the positive and negative terminals of a battery or any other electrical component. - Terminal voltage is affected by the load connected to the source and the internal resistance of the source. - When a load is connected, the terminal voltage is always less than the EMF due to the voltage drop across the internal resistance of the source. In summary, EMF is the voltage generated by a source, voltage drop is the decrease in voltage across a component due to resistance, potential difference is the difference in electric potential energy between two points, and terminal voltage is the voltage measured across the terminals of a source or load in a circuit.
Geotechnical engineers
Edward Teller
Philo Farnsworth
