5. True or False: A beginner should start with long workout sessions and work down to shorter ones.
True
False
Answer:
false...............
Answer:
False A beginners should start from shorter ones to long work sessions
Explanation:
Hope it helps
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ITSMISSBADGURLX2- A copper wire of 3mm diameter with conductivity of 6.7 10' (0.M), and electron mobility of 0.0064 m2 /V sec. Is subjected to an electric field of 30 mV/m. Find (a) the charge density of free electrons, (b) the current density, (c) current flowing in the wire, (d) the electron draft velocity.
Answer:
a) [tex]n=5.98*10^{26}/m^3[/tex]
b) [tex]i=2010000A/m^2[/tex]
c) [tex]I_w=14.207A[/tex]
d) [tex]V_e=1.92*10^{-4}m/s[/tex]
Explanation:
From the question we are told that:
Diameter [tex]d=3mm=>3*10^{-3}[/tex]
Conductivity [tex]\sigma= 6.7 10^7 (0.M),[/tex]
Electron mobility [tex]\phi= 0.0064 m2 /V sec[/tex]
Electric field [tex]E= 30 mV/m[/tex]
a)
Generally the equation for Charge Density is mathematically given by
[tex]\phi=\frac{\sigma}{n e}[/tex]
Therefore
[tex]n=\frac{\sigma}{\phi e}[/tex]
[tex]n=\frac{6.7 10^7}{1.6*10^{-19} *0.0064}[/tex]
[tex]n=5.98*10^{26}/m^3[/tex]
b)
Generally the equation for current density is mathematically given by
[tex]i=\sigma*E[/tex]
[tex]i= 30*10^{-3] *6.7 10^7[/tex]
[tex]i=2010000A/m^2[/tex]
c)
Generally the equation for current in wire is mathematically given by
[tex]I_w=iA[/tex]
[tex]I_w=i*\pi r^2[/tex]
[tex]I_w=(2010000)*\pi( 1.5*10^{-3})^2[/tex]
[tex]I_w=14.207A[/tex]
d)
Generally the equation for electron draft velocity. is mathematically given by
[tex]V_e=\phi E[/tex]
[tex]V_e=(0.0064)*(30*10^{-3})[/tex]
[tex]V_e=1.92*10^{-4}m/s[/tex]
Tres personas, A, B, C, jalan una caja con ayuda de cuerdas cuya masa es despreciable. Si la persona A aplica −3 en dirección horizontal y la persona B aplica a su vez 5 en dirección horizontal, ¿Cuál es el valor de la fuerza que debe ejercer la persona C, para que la caja esté en equilibrio físico?
Answer:
El valor de la fuerza que debe ejercer la persona C debe ser de -2 para que la caja esté en equilibrio físico.
Explanation:
Si la caja debe hallarse en equilibrio físico, entonces se debe satisfacer la siguiente ecuación:
[tex]F_{A} + F_{B} + F_{C} = 0[/tex] (1)
Si sabemos que [tex]F_{A} = -3[/tex] y [tex]F_{B} = 5[/tex], entonces el valor de la fuerza que debe ejercer la persona C debe ser:
[tex]F_{C} = -F_{A}-F_{B}[/tex]
[tex]F_{C} = -(-3)-5[/tex]
[tex]F_{C} = -2[/tex]
El valor de la fuerza que debe ejercer la persona C debe ser de -2 para que la caja esté en equilibrio físico.
4. diference between VR and efficiency
Answer:
Velocity ratio of simple machine is the ratio of distance travelled by effort to the distance travelled by load in the machine. The efficiency of a simple machine is defined as the ratio of useful work done by machine (output work) to the total work put into the machine (input work).
can anyone help me with this one
Answer:
c) sin c /sin d
because light is moving from denser to shallower medium
b) refraction of light
Explanation:
A monatomic gas is measured to have an average speed of 1477 m/s. If the
total amount of the gas is 2 mol (which equates to a mass of 0.008 kg), what
is the approximate temperature of the gas? (Recall that the equation for
kinetic energy due to translation in a gas is KEtranslational = 1 mv2 = 3 nRT,
2
and R = 8.31 J/(mol-K).)
2
Answer:
The temperature of the gas is 350.02 K.
Explanation:
The average speed is related to the temperature as follows:
[tex] \bar v = \sqrt{\frac{3RT}{M}} [/tex] (1)
Where:
[tex] \bar v [/tex]: is the average speed = 1477 m/s
R: is the gas constant = 8.31 J/(K*mol)
T. is the temperature =?
M: is the molar mass
First, let's find the molar mass:
[tex] M = \frac{m}{n} [/tex]
Where:
m: is the mass of the gas = 0.008 kg
n: is the number of moles = 2 mol
[tex] M = \frac{m}{n} = \frac{0.008 kg}{2 mol} = 0.004 kg/mol [/tex]
Hence, by solving equation (1) fot T we have:
[tex] T = \frac{\bar v^{2}*M}{3R} = \frac{(1477 m/s)^{2}*0.004 kg/mol}{3*8.31 J/(K*mol)} = 350.02 K [/tex]
Therefore, the temperature of the gas is 350.02 K.
I hope it helps you!
is a light sensitive screen
Answer:
The retina is the light sensitive focusing screen. Inside, there's two types of fluid, one watery behind the lens, and further back, a thicker one that helps the eyeball hold its shape.
Answer:
The retina is the light sensitive focusing screen.
hope this helps <3
Define potentiol energy , kenetic energy.
Potential energy is stored energy. For example, if a bowling ball is on top of a giant hill, we say it has potential energy because it has the potential to do work which is to roll down the hill.
Kinetic energy is the energy of movement so once that ball rolls down that hill, that potential energy is converted to kinetic energy.
Hey there!
Potential energy and kinetic energy are the two main groups of energy when it comes to all of that. Potential energy is stored energy. Kinetic energy is the energy that is released.
For example, potential energy is when you hold a ball higher than the ground, and kinetic energy is when you release the ball.
Hope this helps! Have a great day! :)
Does water exist on Mars? Explain your answer. Why didn't Jupiter become a star during the early.
Answer:
yes water was discovered in mars
S/REF No. Date If the load distance of a level is 20 cm and effort distance is 6ocm, calculate the amount of effort required to lift a load 200 N.
What is one Pascal pressure? What is its unit?
Explanation:
the force acting perpendicularly on unit area of surface
unit=pascle .
A pressure of one Newton per square meter .. The SI unit of 1 Pascal pressure is 1 Newton per square metre .
A boy shoves his stuffed toy zebra down a frictionless chute. It starts at a height of 1.45 m above the bottom of the chute with an initial speed of 1.23 m/s . The toy animal emerges horizontally from the bottom of the chute and continues sliding along a horizontal surface with a coefficient of kinetic friction of 0.231 . How far from the bottom of the chute does the toy zebra come to rest? Assume g=9.81 m/s2 .
Answer:
The answer is "4.97 m".
Explanation:
[tex]u = 1.23\ \frac{m}{s}\\\\[/tex]
[tex]H= 1.45 \ m\\\\[/tex]
[tex]\mu = 0.231\\\\[/tex]
The law of conservation tells us that heat energy at the top with kinetic energy at the top equals kinetic energy at the base.
[tex]mgh+\frac{1}{2}mu^2=\frac{1}{2}mv^2\\\\2gh +u^2 =v^2\\\\v=\sqrt{u^2+2gh}[/tex]
[tex]v=\sqrt{(1.23\ \frac{m}{s})^2+2(9.81 \frac{m}{s^2}) +(1.45\ m)[/tex]
[tex]=\sqrt{1.5129+19.62 +1.45}\\\\=\sqrt{22.5829}\\\\=4.75\ \frac{m}{s}[/tex]
Friction force is given by the formula
[tex]f=-\mu mg \\\\ma= -\mu mg\\\\a=-\mu g\\\\[/tex]
[tex]= -(0.231) \ (9.81\ \frac{m}{s^2})\\\\=-2.26611 \ \frac{m}{s^2}[/tex]
Now by using an equation of motion as
[tex]v^2-u^2= 2as[/tex]
From the above the distance traveled is
[tex]S=\frac{v^2-u^2}{2a}[/tex]
[tex]S=\frac{(0)^2-(4.75\ \frac{m}{s})^2}{2(-2.26611\ \frac{m}{s^2})}\\\\[/tex]
[tex]=\frac{-(4.75\ \frac{m}{s})^2}{2(-2.26611\ \frac{m}{s^2})}\\\\=\frac{-22.5625}{-4.53222}\\\\=4.97[/tex]
In other words, the distance from the bottom of the chute to the point where the toy zebra comes to rest is [tex]s = 4.97\ m[/tex]
what are the factors of evaporation and give explanation
Answer:
The three primaryfactors of evaporation are heat, atmospheric pressure (which determines the percentage of moisture) and the movementofair. At the molecular level, there is no strict boundary between the liquid state and the vapor state
True or False. A compound is formed when two or more elements are combined to make a new substance with
its own properties
True
Fase
HELP ASAP!!!
What size object (impactor) may create such a crater?
Answer:
I HOPE IT WILL HELP YOU.
:D
What acceleration is produced on a mass of 200g, when a force of 10N is exerted on it?
Answer:
f=ma......10N=0.2a....=50m/s
Answer:
here,
force = mass× acceleration
10 = 0.2 kg × a
or, 10/0.2=a
or, a = 50km/h^2
is the required ans .
Wagonium-292 has a half-life of 1 hour. If you started with an 80 gram sample, how much Wagonium-292 will remain after 4 hours? A.) 10g B.) 40g C.) 160g D.) 5G
After 1 hour, 80 g decays to 40 g.
After another hour (total 2 hours), 40 g decays to 20 g.
After another hour (total 3), 20 g decays to 10 g.
After one more hour (total 4), 10 g decays to (D) 5 g.
Two boys X and Y each have the same total weight
and are standing on soft ground.
Which boy is more likely to sink into the soft ground and
why?
boy more
likely to sink
pressure on soft
ground
А
Х
larger than Y
B
Х
smaller than Y
C
Y
larger than X
D
Y
smaller than X
Answer:
the child with the smallest area will be the one who sinks
Explanation:
The child who will sink to the ground is the one who exerts the greatest pressure on the ground, even though the force, which in this case is equal to the weight, is equal.
Pressure is defined by
P = F / A
in this case the strength of the children is their weight
F = W
P = W / A
therefore the pressure changes are in the area of contact with the ground, the child with the smallest area will be the one who sinks
Explanation of the physics involved i the northern lights(aurora borealis) why can't it occur in mire southerns latitudes?
Answer:
The northern lights come from the interaction of electrically charged particles given off by the Sun surface during solar storms and the Earth's magnetic field which is pointed in the northern to southern poles of the Earth. Therefore, the charged particles that travel through millions of miles from the Sun to the Earth accelerate towards the magnetic poles and appear as the northern (and southern) lights
Boreal is an adjective word for the north or northern regions. In the southern latitudes, in the southern hemisphere, the phenomenon is called aurora australis (australis is the adjective for 'of the south')
Explanation:
the unit of force and pressure are called derived unit
Answer:
yes
Explanation:
because they can be derived in the form of base units
If a ball has a mass of 5 kg and 100 J of KE, what is its velocity?
[tex]{\fcolorbox{white}{lightgreen}{\bf{\textcircled{$\checkmark$}}{Verified\:answer}}}[/tex]
Mass of ball=m=5kgKinetic energy=KE=100JVelocity=v=?We know
[tex]\boxed{\sf K.E=\dfrac{1}{2}mv^2}[/tex]
[tex]\\ \sf\longmapsto 100J=\dfrac{1}{2}5\times v^2[/tex]
[tex]\\ \sf\longmapsto v^2=100\times \dfrac{2}{5}[/tex]
[tex]\\ \sf\longmapsto v^2=20(2)[/tex]
[tex]\\ \sf\longmapsto v^2=40[/tex]
[tex]\\ \sf\longmapsto v=\sqrt{40}[/tex]
[tex]\\ \sf\longmapsto v=6.2m/s[/tex]
Answer:
6.2m/s
Explanation:
What is the dimension of Gravitation constant h?
[tex]\\ \sf\longmapsto Gravitational\:Constant(G)[/tex]
[tex]\\ \sf\longmapsto \dfrac{Force\times (distance)^2}{Mass\times Mass}[/tex]
[tex]\\ \sf\longmapsto \dfrac{\left[MLT^{-2}\right]\left[ML^1T\right]^2}{\left[M^1LT\right]\left[M^1LT\right]}[/tex]
[tex]\\ \sf\longmapsto \left[M^{-1}L^3T^{-2}\right][/tex]
Answer:
Or, G = [M1 L1 T-2] × [L]2 × [M]-2 = [M-1 L3 T-2]. Therefore, the gravitational constant is dimensionally represented as M-1 L3 T-2.
Explanation:
Hope it help you
A spring has a spring constant of 5 N/m and is stretched 10 m. What its U,?
a. 50 J
b. 70 J
c. 90 J
d. 250 J
Answer
I am not sure but it is may be 50J
I hope that's, this answer is fine.
pleeease help meeeeee
during a journey, a car travels at 40 km in 2.5 hours, next 62 km in 3 hours, then took a break for 30 minutes, again travelled the last 120 km in 3.2 hours. calculate the average speed of the car during the journey.
10. Explain the principle of electric motor. Write its uses.
Explanation:
The principle of an electric motor is based on the current carrying conductor which produces magnetic field around it. A current carrying conductor is placed perpendicular to the magnetic field so that it experiences a force.
The largest electric motors are used for ship propulsion, pipeline compression and pumped-storage applications with ratings reaching 100 megawatts. Electric motors are found in industrial fans, blowers and pumps, machine tools, household appliances, power tools and disk drives.
Question 4: Scientists and engineers often plan investigations to see how changing one variable affects the outcome. A variable is any trait, condition or feature of something being tested. Imagine a team is testing the speed of a toy car. In trial 1, they test the car and measure how long it takes it to travel 2 meters. In trial 2, they want to investigate how changing a variable affects the car's speed. Which of the following plans is BEST for trial 2?
A variable, as its name implies, is something that can change, ideally, as the scientists and engineers want to.
Particularly we care for the independent variables, which are the ones we can control and affect the dependent variables, which are the outcomes we study.
For a quick example, think of an experiment where you heat something on an oven. The temperature of the oven can be set by the scientist, so the temperature is an independent variable because they can control it.
Now let's see the given experiment.
The team is testing the speed of the toy car.
remember that:
distance/time = speed.
We know that in the first trial, they test how long takes the car to travel 2 meters.
Now, what we can change for the second trial, knowing that the speed is the output that we are studying?
The answer is trivial, the only thing we can change in the given setup is the distance that the car travels, so in the next trial we should change the variable "distance travelled by the car" and see if it affects the output "speed of the car".
If you want to learn more about variables, you can read:
https://brainly.com/question/19585043
help i need to answer this question fast
Answer:
The reason you feel weightless is because there is no force pushing against you, since you are not in contact with anything. Gravity is pulling equally on all the particles in your body. This creates a sensation where no forces are acting on you and you feel weightless.
set up differential equation of angular S.H.M
Answer:
[tex]{ \sf{ \omega \: is \: the \: angular \: velocity}} \\ { \sf{ \theta \: is \: the \: angular \: displacement}}[/tex]
Determine whether the vector field is conservative. If it is, find a potential function for the vector field.
Answer:
Electric field intensity is not conservative vector
Explanation:
Only electrostatic fields i.e. fields generated by a static charge distribution, are conservative in nature
Give reason Pascal is a derived unit
The pascal is the SI derived unit of pressure used to quantify internal pressure, stress, Young's modulus and ultimate tensile strength.
Symbol ⇥ Pa