Define and describe four ways in which fluorescence excitation is more sensitive than optical absorption.
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A professional boxer hits his opponent with a 1345-N horizontal blow that lasts for 0.122 s.
a) Calculate the impulse (in kg · m/s) imparted by this blow.
b) What is the opponent's final velocity (in m/s), if his mass is 113 kg and he is motionless in midair when struck near his center of mass?
c) Calculate the recoil velocity (in m/s) of the opponent's 11.4 kg head if hit in this manner, assuming the head does not initially transfer significant momentum to the boxer's body.
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A point charge of -2.5 µC is located at the origin. A second
point charge of 11 µC is at x = 1 m, y = 0.5 m.
Find the x and y coordinates of the position at
which an electron would be in equilibrium.
x = m
y = m
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A thin rod consists of two parts joined together. One-fourth of it is silver and three-fourths is gold. The temperature decreases by 22 C°. ΔL/(L0,Silver + L0,Gold) Determine the fractional decrease in the rod's length using the formula above, where L0,Silver and L0,Gold are the initial lengths of the silver and gold rods.
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What are the 3 types of boundary effects and give a basic description of each?
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Two resistors, R1 = 20-ohm and R2 = 30-ohm, are connected in parallel to each other, and this combination is connected across a 30-V source of emf. The current through the resistor R2 is:
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Consider an experiment with a beam of relativistic particles hitting a target. Show that the cross-sectional area perpendicular to the direction of the beam propagation is a relativistic invariant.
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Explain the differences between primary electrons, secondary electrons, Auger electrons, and backscattered electrons and how they are used in SEM imaging and analysis.
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Briefly explain the following terms in a few sentences:
a. Resolution of optical microscopy
b. Langmuir versus Langmuir-Blodgett (LB) film
c. The wavelength of electrons at an acceleration voltage of 100 kV
d. Chemically amplified photoresist
e. Elastic versus inelastic scattering
f. Capillary force
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A block of mass m1 = 6 kg on a rough 30°-inclined plane is connected to a 4-kg mass (m2) by a string of negligible mass passing over a pulley shaped like a ring. The 2-kg pulley has radius 20 cm and rotates about its symmetry axis of rotation. The string causes the blocks and the pulley to rotate without slipping and without friction. The 6-kg block (m1) on the 30°slope is initially pressed against a spring near the bottom of a long rough incline, compressing the spring by 50 cm. The spring is not attached to the block and has a spring constant is 500 N/m. When the system is released, the spring returns to its equilibrium length as it projects the 6-kg block (m1) toward the top of the incline. Assume that the spring just loses contact with the block (m1) at the instant it returns to its equilibrium length. The coefficient of kinetic friction between the block (m1) and the surface of the incline is 0.2. By considering the conservation of energy and any other suitable methods: (a) Calculate the speed of the blocks at the instant the spring first returns to its equilibrium length. [v = 3.2 m/s] (b) What is the total angular momentum of the system when the spring first returns to its equilibrium length? [7.7 kg.m2/s] (c) By considering the total angular momentum of the system, find the rate of change of the angular momentum of the system after the blocks lose contact with the spring. [-0.08 m.N] (d) What is the net torque causing the angular acceleration of the system after the blocks lose contact with the spring? [-0.08 m.N]
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Workers have loaded a delivery truck in such a way that its center of gravity is only slightly forward of the rear axle, as shown in the figure. The mass of the truck and its contents is 6960 kg. Find the magnitudes of the forces exerted by the ground on (a) the front wheels and (b) the rear wheels of the truck.
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The cart rolls down an incline. The launcher fires the ball in a direction perpendicular to the cart. Show that the ball lands back in the cart.
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I need to make a final grade 12 physics presentation about everything that i have learned, it can be anything
the question: Describe what you learned in every unit and
whether or not you were able to
meet those expectations. (E.g. what are some topic(s) in each unit
course that
you feel you understand well or skills you excelled at?).
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Describe the evolution of a 20 M⊙ star. A H-R diagram must be drawn, and key aspects must be described in detail. Highlight how the star’s evolution will differ from that of the Sun
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We have a simple harmonic motion that is described by the equation: ? (?) = 0.82cos (0.4? + 0.2) Determine the equation of v (t) and a (t).
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