The uncertainty principle arises from a common-sense idea: To measure something, you must affect it somehow. For instance, when you use a pressure gauge to measure air pressure in a car tire you release a small amount of air into the gauge.

• Why does shining very short wavelength photons on an electron not tell you exactly where the electron is?
• Describe two other examples of situations in which measuring something about an object somehow changes it.

An object is placed 68cm from a screen

1. At what point from the object should a converging lens with a focal length of 17cm be placed so that it will produce a sharp image on the screen? (in cm   from the object)

2. What is the image's magnification?

In this example we will apply the equations for constant angular acceleration to the simple case of a rotating bicycle wheel. The angular velocity of the rear wheel of a stationary exercise bike is ω0=4.00rad/s at time t=0, and its angular acceleration is constant and equal to α=2.45rad/s2. A particular spoke coincides with the +x axis at time t=0 (Figure 1). What angle does this spoke make with the +x axis at time t=3.00s? What is the wheel's angular velocity at this time? part A: How much longer will it take before the reference spoke is once again aligned with the +x axis? Part B: What will the angular speed of the wheel be at this time?

A small object is placed to the left of a convex lens and on its optical axis. The object is 50 cm from the lens, which has a focal length of 15 cm. Determine the location of the image formed by the lens. (Enter your answer in cm from the lens.)

_____ cm from the lens

Describe the image. (Select all that apply.)

real ____

Virtual ___

upright ____

Inverted ___

enlarged ___

Reduced ___

on the left side of the lens ___

on the right side of the lens __

A 64.7-kg skateboarder starts out with a speed of 2.44 m/s. He does 119 J of work on himself by pushing with his feet against the ground. In addition, friction does -257 J of work on him. In both cases, the forces doing the work are non-conservative. The final speed of the skateboarder is 7.88 m/s. (a) Calculate the change (PE_f - PE₀) in the gravitational potential energy. (b) How much has the vertical height of the skater changed? Give the absolute value.

In the shot put, a heavy lead weight—the "shot"—is given an initial velocity, starting from an initial elevation approximately equal to the shot putter's height, say, 1.96 m. If v₀ = 8.70 m/s, find the horizontal distance traveled by the shot for the following initial angles above the horizontal.

(a) θ₀ = 0°


(b) θ₀ = 40.0°


(c) θ₀ = 45.0°

The mass of the nuclide 16/8O is 15.995u .

A) What is the total binding energy for this nucleus?

Eb =     MeV  

B) Determine its average binding energy per nucleon.

Eb/A= Mev/nucleon

Coulumb's law for the magnitude of the force F between two particles with charges Q and Q' separated by a distance d is

F=K * qq'/d^2    where K= 1/4pie e0 and e0= 8.854*10^-12/ (N*m^2) is the permittivity of free space.

Consider two point charges located on the x axis: one charge,

q1 = -16.0nC , is located atx1 = -1.700m ; the second charge, q2 = 38.5nC ,is at the origin (x=0.0000).

question 6) A 501.0-nm light source illuminates two slits with a separation of 6.00 ✕ 10⁻⁴ m, forming an interference pattern on a screen placed 4.30 m away from the slits. At a point a distance of 3.85 mm from the central maximum, what are the following?

(b) the intensity compared to that of the central maximum

Question 7) In a Young's double-slit experiment, 610-nm-wavelength light is sent through the slits. The intensity at an angle of 2.80° from the central bright fringe is 85% of the maximum intensity on the screen. What is the spacing between the slits?

Question 6 part b and question 7

A 0.47 kg banana is thrown directly upward with an initial speed of 4.3 m/s and reaches a maximum height of 0.90 m. What change does air drag cause in the mechanical energy of the banana–Earth system during the ascent?

A wire has a resistivity of 6.80 x 10-8 ohm . meter when the temperature is 75.0 degrees Farenheit. If the temperature coefficient of resistivity of the material that the wire is made from is 5.0 x 10-3 (1/Kelvin), what will be the resistivity of the wire when it is cooled to 45.0 degrees Farenheit? Note: before working this problem you must convert the temperature from the Farenheit temperature scale to the Kelvin scale. Give your answer in the form "a.bc" x 10-8 Ω.m.

(2) A heating element is made by maintaining a potential difference of 13.5 V along the length of a certain wire with a 6.80 x 10^-6 m² cross section area and a resistivity of 4.68 x 10^-6 ohm.m. If the element dissipates 5.0 W, what is its length? Put your answer in the form of "a.bc x 10^(x) m"

(3)a potential difference of 12.8 V is maintained between the ends of a 1500 cm length of wire whose diameter is 0.56 mm. The conductivity of the wire is 4.80 x 10⁷(ohm.m)^-1. Determine the rate at which energy in the wire is transformed from kinetic to thermal energy. Give your answer in the form "a.bc x 10^(x) unit".

(4)A current of 126 mA exists in a wire for 5.60 minutes. What is the rate that charge passes a point in the wire? Give your answer in the form "a.bc x 10^(x)" C/s. Continuing the previous question, what is the rate of electrons passing through a cross section perpendicular to the wire's axis? Give your answer in the form "a.bc x 10^(x)" electrons/second. Assume that the charge moves in a straight line from one end of the wire to the other, how many electrons are moved through the cross section during 38.0 ms? Give your answer in the form "a.bc x 10^(x)" electrons

(5) An electrical current of 8.50 mA exists in a solid cylindrical wire whose diameter is 1.50 mm. Calculate the magnitude of the current density in the wire. Put your answer in the form of "a.bc x 10^(x)" A/m².  Assume that electrons are the charge carriers and the conduction electron density is 8.55 x 10²⁹/m³. (Note that this is the charge carrier density and could also be stated as 8.55 x 10²⁹ charge carriers/m³ or electrons/m³.) Calculate the electron drift speed in the wire. Put your answer in the form of "a.bc x 10^(x) m/s".

(6.)A wire with a resistance of 6.80 mΩ is drawn out through a die so that its new length is 4 times its original length. Find the resistance of the longer wire, assuming that the resistivity and density of the material are not changed during the drawing process. Put your answer in the form of "a.bc x 10^(x) ohm".

A plane electromagnetic wave, with wavelength 3.5 m, travels in vacuum in the positive direction of an x axis. The electric field, of amplitude 440 V/m, oscillates parallel to the y axis. What are the (a) frequency, (b) angular frequency, and (c) angular wave number of the wave? (d) What is the amplitude of the magnetic field component? (e) Parallel to which axis does the magnetic field oscillate? (f) What is the time-averaged rate of energy flow associated with this wave? The wave uniformly illuminates a surface of area 2.3 m2. If the surface totally absorbs the wave, what are (g) the rate at which momentum is transferred to the surface and (h) the radiation pressure?

The drawing shows a square, each side of which has a length of L = 0.250 m. Two different positive charges q1 and q2 are fixed at the corners of the square. Find the electric potential energy of a third charge q3 = -4.00 x 10-9 C placed at corner A and then at corner B.

------------------------------------------------------------------------------------------------------------------------------------sfdgsdfgfd-------------------------------sfgsfd-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------gsdfgfd-------------------------------sfgsfdgsdfgfd-------------------------------sfgsfdgsdfgfd-------------------------------sfgsfd----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------gsdfgfd-------------------------------sfgsfdgsdfgfd-------------------------------sfgsfdgsdfgfd-------------------------------sfgsfdgsdfgfd-------------------------------sfgsf--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------dgsdfgfd-------------------------------sfgsfdgsdfgfd-------------------------------sfgsfdgsdfgfd-------------------------------sfgsfdgsdfgfd-------------------------------sfgsfdgsdfgfd--------------------------sfg----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------sfdgsdfgfd-------------------------------sfgsfd-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------gsdfgfd-------------------------------sfgsfdgsdfgfd-------------------------------sfgsfdgsdfgfd-------------------------------sfgsfd----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------gsdfgfd-------------------------------sfgsfdgsdfgfd-------------------------------sfgsfdgsdfgfd-------------------------------sfgsfdgsdfgfd-------------------------------sfgsf--------------------------------------------------------------------------------------------------

1. A Capacitor is discharging through a resistor. When the capacitor has lost a quarter of its charge, the voltage across the resistor is:
A) greater than the voltage across the capacitor.
B) equal to the voltage across the capacitor.
C) Zaro.
D) equal to the sum of the voltages across the battery and the capacitor.
E) less than the voltage across the capacitor, but greater than zero.
2. An air-FIlled parallel-plate capacitor is connected to a battery and allowed to charge up, and then disconnected from the battery. A slab of dielectric material is placed between the plates of the capacitor. After this is done, we find that:
A) the voltage across the capacitor has decreased.
B) the charge on the capacitor has decreased.
C) the charge on the capacitor has increased.
D) the voltage across the capacitor has increased.
E) the energy stored in the capacitor has increased.
I thought Second question answer was E.

Explain in detail, please!

Discuss how the size of details of an object that can be detected with electromagnetic waves is related to the wavelength of the EM wave, by comparing details observable with two different types (for example, radar and visible light or infrared and X-rays).  Would an individual atom be observable by the human eye using a powerful optical microscope (one that uses visible light)? Why don