[link] shows a long straight wire just touching a loop carrying a current
${I}_{1}$ . Both lie in the same plane. (a) What direction must the current
${I}_{2}$ in the straight wire have to create a field at the center of the loop in the direction opposite to that created by the loop? (b) What is the ratio of
${I}_{1}/{I}_{2}$ that gives zero field strength at the center of the loop? (c) What is the direction of the field directly above the loop under this circumstance?
Find the magnitude and direction of the magnetic field at the point equidistant from the wires in
[link] (a), using the rules of vector addition to sum the contributions from each wire.
Find the magnitude and direction of the magnetic field at the point equidistant from the wires in
[link] (b), using the rules of vector addition to sum the contributions from each wire.
What current is needed in the top wire in
[link] (a) to produce a field of zero at the point equidistant from the wires, if the currents in the bottom two wires are both 10.0 A into the page?
10.0 A
Calculate the size of the magnetic field 20 m below a high voltage power line. The line carries 450 MW at a voltage of 300,000 V.
Integrated Concepts
(a) A pendulum is set up so that its bob (a thin copper disk) swings between the poles of a permanent magnet as shown in
[link] . What is the magnitude and direction of the magnetic force on the bob at the lowest point in its path, if it has a positive
$0\text{.}\text{250 \mu C}$ charge and is released from a height of 30.0 cm above its lowest point? The magnetic field strength is 1.50 T. (b) What is the acceleration of the bob at the bottom of its swing if its mass is 30.0 grams and it is hung from a flexible string? Be certain to include a free-body diagram as part of your analysis.
(a) What voltage will accelerate electrons to a speed of
$6\text{.}\text{00}\times {\text{10}}^{-7}\phantom{\rule{0.25em}{0ex}}\text{m/s}$ ? (b) Find the radius of curvature of the path of a
proton accelerated through this potential in a 0.500-T field and compare this with the radius of curvature of an electron accelerated through the same potential.
Integrated Concepts
Find the radius of curvature of the path of a 25.0-MeV proton moving perpendicularly to the 1.20-T field of a cyclotron.
60.2 cm
Integrated Concepts
To construct a nonmechanical water meter, a 0.500-T magnetic field is placed across the supply water pipe to a home and the Hall voltage is recorded. (a) Find the flow rate in liters per second through a 3.00-cm-diameter pipe if the Hall voltage is 60.0 mV. (b) What would the Hall voltage be for the same flow rate through a 10.0-cm-diameter pipe with the same field applied?
Integrated Concepts
(a) Using the values given for an MHD drive in
[link] , and assuming the force is uniformly applied to the fluid, calculate the pressure created in
${\text{N/m}}^{2}\text{.}$ (b) Is this a significant fraction of an atmosphere?
(a) Calculate the maximum torque on a 50-turn, 1.50 cm radius circular current loop carrying
$\text{50 \mu A}$ in a 0.500-T field. (b) If this coil is to be used in a galvanometer that reads
$\text{50 \mu A}$ full scale, what force constant spring must be used, if it is attached 1.00 cm from the axis of rotation and is stretched by the
$\text{60\xba}$ arc moved?
In this morden time nanotechnology used in many field .
1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc
2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc
3- Atomobile -MEMS, Coating on car etc.
and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change .
maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
can nanotechnology change the direction of the face of the world
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.