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.

How do random motion and gravitational collapse combine to convert giant molecular clouds into open star clusters over a long period of time?

To describe and analyze motion in 2D (or higher), the use of vectors is the common method used. From your work with vectors, past and present, do you find the vector method a good (even best) way to analyze quantities in 2D? Are there other methods that could be used that will give the same results? From your own experience, what are the pros and cons in using the vector method?

Please no handwritten or typed responses - only typed answers.

Describe house wiring and specify how parallel or series connections of bulbs and resistors affect the functions.

A 72.0 kg swimmer jumps into the old swimming hole from a tree limb that is 3.95 m above the water.

Use energy conservation to find his speed just as he hits the water if he just holds his nose and drops in.

Express your answer to three significant figures.

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Part B

Use energy conservation to find his speed just as he hits the water if he bravely jumps straight up (but just beyond the board!) at 2.60 m/s .

Express your answer to three significant figures.

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Part C

Use energy conservation to find his speed just as he hits the water if he manages to jump downward at 2.60 m/s .

Express your answer to three significant figures.

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A kestrel dives from a stationary hover, 20 m above the ground, to catch its prey, typically mice, on the ground. (a) If the kestrel’s acceleration toward the ground is due solely to free fall, calculate how long it takes to reach the ground. (3 points) (b) A field mouse can run at a top speed of 10 km/h, which it achieves starting from rest in 1 s. Assuming that the only way for the mouse to survive the kestrels attack is to find shelter, calculate the maximum distance the mouse can be from shelter to survive if it sees the kestrel as it begins its dive. (3 points) The mouse, in fact, only first sees the kestrel when it is at the mid point of the dive 10m above the ground. (c) Based only on your intuition (and not on any calculation), estimate how far the mouse needs to be from shelter to survive now. (1 point) (d) Calculate how far the mouse needs to be from shelter to survive in the new situation.

what is the frequency of a sound wave made by