This week two big concepts discussed are electric fields and electric potential, with electric potential being the basis for voltage. Along with the general discussion of these concepts, some interesting and common applications were briefly talked about like copiers, printers, TVs, etc.

Can you find two examples - one for electric field, one for electric potential - that are connected to the field of biology

Please no handwritten or picture responses - only typed replies.

Suppose you are viewing some red light coming from a galaxy far, far away. The wavelength of the red light is expected to be 6300 nm if the relative speed of the galaxy with respect to your world is zero. That is, if the galaxy and you are not moving toward or away from each other. However, you observe a wavelength that is longer than expected. How would you interpret this observation?     Recall the frequency dependence of the Doppler shift: f’ = f (1 ⁺ u/c).

Compare and contrast alpha and beta decay.

What type of decay should 32Si undergo, and why?

A cube with side length L, and density ρ_C sits at rest on a bathroom scale at the bottom of a large tank. The tank is partially filled with a fluid having density ρ_f, leaving the cube partially submerged. A side profile view of the cube shows the cube face a distance d outside of the fluid, and a distance L-d submerged under the fluid. Determine the distance dwhen ρ_f= 2000 kg/m³, ρ_C= 4000 kg/m³and L = .50 m. Write every step with detail specially when solving for the unknown, since I am trying to learn how to do it and also draw a diagram.

Red light of wavelength 675 nm is incident on a slit of width 4.56 × 10−6 m. An observing screen is placed 1.50 m from the slit.

9a) Find the distance between the third order dark fringe and the central bright fringe (in meters).

9b) If you replaced the single slit with two slits centered on the former position of the single slit, what would the separation between the two slits need to be in order for the second order bright fringe of the double-slit interference pattern to fall on the third order dark fringe of the single slit diffraction pattern?

9c) If the average adult pupil diameter is 3.5 mm, what distance from the observing screen is a person no longer able to resolve (distinguish) the second order bright fringe and the central bright fringe in the double slit interference pattern?

Consider a point charge +q. A) Sketch the electric field lines and equipotetial lines near the charge. B) Explain how to interpret these equipotential lines. In other words, what does electric potential mean in terms of work? C) Indicate the direction of increasing potential in your sketch. D) Consider one potential line in your sketch. How much work is required to move a charge anywhere along that line.

A 2.18e-9 C charge has coordinates x = 0, y = −2.00; a 2.76e-9 C charge has coordinates x = 3.00, y = 0; and a -4.95e-9 C charge has coordinates x = 3.00, y = 4.00, where all distances are in cm. Determine magnitude and direction for the electric field at the origin and the instantaneous acceleration of a proton placed at the origin.

1-A bullet moving horizontally with a speed of 600 m/s strikes a sandbag and continues for a distance of 20 cm.

A-What is the average acceleration of the bullet?

B-How long does it take to come to rest?

2-A 45.0 kg skier, starting from rest, begins skiing straight down an incline on the mountain of 12.5. The coefficient of kinetic friction between skis and snow is 0.08.

A-Draw a free body diagram of the skier and the forces acting on the skier.

B-Calculate the Normal force acting on the skier

C-Calculate the force of kinetic friction acting on the skier

D-Calculate the acceleration of the skier

E-The skier travels a distance of 150 m down the mountain. What is her final speed after 150?

Compare and contrast the relativistic and classical expressions for the kinetic energy of an object.

How does the relativistic expression explain the impossibility of an object to reach the speed of light?

Retrograde motion of superior planet always occurs when the planet is a) in conjunction with the moon b)brighter than average c)near the autumnal equinox d) near a solstice e) dimmer than average 2) The moon a) spins once on its axis relative to the sun every 23 hours 56 mins. b) spins once on it axis relative to the sun every 24 hours c) spins once on its axis relative to the sun every 29.5 days d) spins once on its axis relative to the sun every 365 days e)never spins on its axis 3) The planets a) move faster in their orbit around the sun in km/s, the closer they are to the sun b) are always located at the same right ascension and declination in the sky c) are always found along the celestial equator d) are always located at declinations greater than 60 degrees e) are always observed along the meridian

In the 2016 Olympics in Rio, after the 50 m freestyle competition, a problem with the pool was found. In lane 1 there was a gentle 1.2 cm/s current flowing in the direction that the swimmers were going, while in lane 8 there was a current of the same speed but directed opposite to the swimmers' direction. Suppose a swimmer could swim the 50.0 m in 25.0 s in the absence of any current.

Part A: How would the time it took the swimmer to swim 50.0 m change in lane 1?

Part B: How would the time it took the swimmer to swim 50.0 m change in lane 8?

Two identical point charges, each of charge +2.00x10-6 C and mass 7.00x10-6 kg , are fixed on the y-axis at the points (x,y) = (0, +3.00) meters and (x,y) = (0, -3.00) meters. Suppose a negative charged particle of mass 8.00x10-9 kg and of charge – 6.00 C is released from rest on the x-axis at the point (x,y) = (- 4.00, 0) meters. What will be the speed of the negative charge at the instant it passes though the origin of the coordinate system?

Gayle runs at a speed of 3.30 m/s and dives on a sled, initially at rest on the top of a frictionless snow-covered hill. After she has descended a vertical distance of 5.00 m, her brother, who is initially at rest, hops on her back and together they continue down the hill. What is their speed at the bottom of the hill if the total vertical drop is 15.0 m? Gayle's mass is 47.0 kg, the sled has a mass of 5.25 kg and her brother has a mass of 30.0 kg.

A block with mass m1 = 9.4 kg is on an incline with an angle θ = 34° with respect to the horizontal. For the first question there is no friction between the incline and the block. 1) When there is no friction, what is the magnitude of the acceleration of the block? m/s2 2) Now with friction, the acceleration is measured to be only a = 3.73 m/s2. What is the coefficient of kinetic friction between the incline and the block? 3) To keep the mass from accelerating, a spring is attached with spring constant k = 168 N/m. What is the coefficient of static friction if the spring must extend at least x = 16 cm from its unstretched length to keep the block from moving down the plane? 4) The spring is replaced with a massless rope that pulls horizontally to prevent the block from moving. What is the tension in the rope? N 5) Now a new block is attached to the first block. The new block is made of a different material and has a coefficient of static friction μ = 1.01. What minimum mass is needed to keep the system from accelerating? kg

A 6.60 −μC particle moves through a region of space where an electric field of magnitude 1350 N/C points in the positive x direction, and a magnetic field of magnitude 1.25 T points in the positive z direction. If the net force acting on the particle is 6.21×10−3 N in the positive x direction, find the components of the particle's velocity. Assume the particle's velocity is in the x-y plane.