A spherical shell with radius R and superficial charge
density,
It rotates around the z-axis through its center with a constant
angular frequency.
The magnetic field formed in the center as a result of the rotation
of the spherical shell
Found it.
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A cylindrical conductive shell with radius a and height h
Total i0 flow passes counterclockwise from the surface.
The stream is homogeneously distributed over the lateral surface of
the cylinder. Cylinder
formed on the axis and at the middle point (O point) of the upper
surface
Find the magnetic field.
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Did you know that diesel engines don’t have spark plugs? The cycle that diesel engines undergo involves adiabatically compressing the air in the cylinder, then injecting some fuel. When the fuel is injected it ignites if the temperature of the air in the cylinder is above the fuel’s flashpoint. Most diesel engines have a compression ratio (the ratio of the maximum to minimum volume) between 14:1 and 25:1.
a) For the given range of compression ratios, what is the range of maximum temperature (in oC) of the air in the cylinder, assuming the air is taken into the cylinder at 20oC?
b) Most gasoline engines today have compression ratios of 8:1. Explain why a diesel engine requires a better more efficient cooling system than a gasoline engine.
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How much ice is needed to make ice tea at a temperature of 50 C from 140 grams of hot tea at 650 C contained in a glass container of 50 gm with specific heat equal to 0.2 cal/gm0 C. Treat the tea as colored water.
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A 2 kg ball moving W at 5 m/s collides head on with a 1.5 kg ball moving E at 8 m/s. Ifthe collision is elastic, compute the velocity of each ball after the collision.
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Show the Biot Savart law for current density satisfies magnetostatic equation
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Two optical fibers have an attenuation of 10 dB and 15dB. Prove that the attenuation will be 25dB if they joined end-to-end.
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Q.7 MRI machine uses magnetic field to create detailed
images of human soft organs. Can you
elaborate the basic concept of working of MRI scanner? How the
strong magnetic field is
produced in MRI scanner to scan the organs? Discuss the role of
radio waves in MRI machines?
Write down major parts used in MRI machine. What would happen if
the north-pole end of a bar
magnet is held near a positively charged piece of plastic? Justify
your answer. X-ray machine
and MRI machine do the same job of human organ scanning. Analyze
both the machines and
discuss three merits and demerits of it.
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When you examine the calculated power outputs, how does the Lewis equation compare with the Johnson average and the Harman average power equations? With the Johnson and Harman peak power equations? The Sayers equation? If differences exist between the results for the various formulas, explain what may contribute to these differences. (Equations are for countermovement and static vertical jump power equation)
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Give your recommendation about the concept of specific
heat capacity and latent heat can
be utilized in ice- cream industry to cool the ice creams and in
cooking food in the kitchen. In the
latent heat formula, Q = ± mL, how can you make the significance of
dual sign in the formula?
How can you provide scientific justifications to prove that there
are some differences in total
cooking time in open vessels compared that with a closed vessel
like pressure cooker
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A mass of 20 grams stretches a spring 5cm. Suppose that the mass is also attached to a damper with constant coefficient 0.4 N·s/m. Initially the mass is pulled down an additional 2cm and released. Write a differential equation for the position u(t) of the mass at time t (make the units meters, kilograms, Newtons, seconds). Do NOT solve the differential equation.
The solution to a differential equation that models a vibrating spring is u(t) = 4e−t cos(3t) + 3e−t sin(3t) + 51 cos(2t) + 25 sin(2t) .
(b) Determine the transient part of the solution.
(c) Determine the phase, quasi-amplitude, quasi-frequency,
quasi-period. (d) Determine the steady state part of the
solution.
(e) Determine the phase, amplitude, frequency, period. of the
steady part of the solution.
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Two lab partners, Mary and Paul are both farsighted. Mary has a near point of 6.7 cm from her eyes and Paul has a near point of 130 cm from his eyes. Both students wear glasses that correct their vision to a normal near point of 25.0 cm from their eyes, and both wear glasses 1.80 cm from their eyes. In the process of wrapping up their lab work and leaving for their next class, they get their glasses exchanged (Mary leaves with Paul's glasses and Paul leaves with Mary's glasses). When they get to their next class, find the following.
(a) Determine the closest object that Mary can see clearly (relative to her eyes) while wearing Paul's glasses. m
(b) Determine the closest object that Paul can see clearly (relative to his eyes) while wearing Mary's glasses. m
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