A -8.50 nC point charge and a +17.0nC point charge are 17.5 cm apart on the x-axis.

What is the electric potential at the point on the x-axis where the electric field is zero?

What is the magnitude of the electric field at the point on the x-axis, between the charges, where the electric potential is zero?

A playground is on the flat roof of a city school, 6.5 m above the street below (see figure). The vertical wall of the building is h = 7.80 m high, forming a 1.3-m-high railing around the playground. A ball has fallen to the street below, and a passerby returns it by launching it at an angle of θ = 53.0° above the horizontal at a point d = 24.0 m from the base of the building wall. The ball takes 2.20 s to reach a point vertically above the wall. (a) Find the speed at which the ball was launched. (Give your answer to two decimal places to reduce rounding errors in later parts.) m/s (b) Find the vertical distance by which the ball clears the wall. m (c) Find the horizontal distance from the wall to the point on the roof where the ball lands.

Two 10-cm-diameter charged rings face each other, 20.0 cmapart. Both rings are charged to + 10.0 nC . What is the electric field strength

A.)at the midpoint between the two rings?

B.)at the center of the left ring?

How does fluoroscopy work? (to answer this properly you will need to draw a diagram and explain how it works; brief answers won't be acceptable). Be sure to explain in detail how the image intensifier works. Assu

1. Before working this problem, review Conceptual Example 14. A pellet gun is fired straight downward from the edge of a cliff that is 12 m above the ground. The pellet strikes the ground with a speed of 28 m/s. How far above the cliff edge would the pellet have gone had the gun been fired straight upward?

_______________________ m

2.  An astronaut on a distant planet wants to determine its acceleration due to gravity. The astronaut throws a rock straight up with a velocity of +10 m/s and measures a time of 24.1 s before the rock returns to his hand. What is the acceleration (magnitude and direction) due to gravity on this planet? (Indicate direction by the sign of the acceleration.)

_________________ m/s²

An unmarked police car traveling a constant 85 km/h is passed by a speeder traveling 139 km/h . Precisely 1.00 s after the speeder passes, the police officer steps on the accelerator; if the police car's acceleration is 2.40 m/s2 , how much time passes after the police car is passed by a speeder and before the police car overtakes the speeder (assumed moving at constant speed)?

11)Two books are stacked on a table and are at rest. Hitchhiker’s Guide to the Galaxy lies on top of War and Peace which sits on the table. War and Peace is much heavier than Hitchhiker’s Guide to the Galaxy. Draw a free body diagram for each book. >> 12)The author Tolstoy claims: “The weight of Hitchhiker’s Guide to the Galaxy is a force that acts on War and Peace.” Is this correct? Explain your answer. >> 13)The author Douglas Adams states that there is only one force acting on Hitchhiker’s Guide to the Galaxy and the only reason that it does not move is because War and Peace is in the way. Is this correct? Explain your answer.

The New York Wheel is the world's largest Ferris wheel. It's 183 meters in diameter and rotates once every 37.3 min.

1.Find the magnitude of the average velocity at the wheel's rim, over a 7.80-min interval.

2.Find the magnitude of the average acceleration at the wheel's rim, over a 7.80-min interval.

3.Find the magnitude of the wheel's instantaneous acceleration.

4.Determine the ratio of the difference between the magnitude of the wheel's instantaneous acceleration and the magnitude of the average acceleration to the magnitude of the average acceleration.

You are given a vector in the xy plane that has a magnitude of 89.0 units and a y component of -64.0 units.

A) Assuming the x component is known to be positive, specify the magnitude of the vector which, if you add it to the original one, would give a resultant vector that is 80.0 units long and points entirely in the −x direction.

B) Specify the direction of the vector.

The giant squid axon has a diameter of 100μm, a membrane thickness of 7.5nm, and a specific membrane capacity of 1μF/cm2. Draw a schematic of the axon, local charge distributions, and indicate the electric field vector across the membrane at rest. Calculate the magnitude of the electric field across the membrane.

Two systems are in oscillation: a simple pendulum swinging back and forth through a very small angle and a block oscillating on a spring. The block-spring system takes twice as much time as the pendulum to complete one oscillation. Which of the following changes could make the two systems oscillate with the same period?

A. Increasing the mass of the pendulum bob

B. Increasing the angle through which the pendulum swings by a small amount

C. Decreasing the mass of both the block and the pendulum bob

D. Shortening the pendulum

A rock is thrown off a cliff at an angle of 46° above the horizontal. The cliff is 120 m high. The initial speed of the rock is 21 m/s. (Assume the height of the thrower is negligible.)

(a)

How high above the edge of the cliff does the rock rise (in m)?

(b)

How far has it moved horizontally when it is at maximum altitude (in m)? m

(c)

How long after the release does it hit the ground (in s)?

(d)

What is the range of the rock (in m)?

(e)

What are the horizontal and vertical positions (in m) of the rock relative to the edge of the cliff at

t = 2.0 s,

t = 4.0 s,

and

t = 6.0 s?

(Assume the +x-direction is in the horizontal direction pointing away from the cliff, the +y-direction is up towards the sky, and x = y = 0 at the point from which the rock is thrown.)

mx(2.0 s)=

my(2.0 s)=

mx(4.0 s)=

my(4.0 s)=

mx(6.0 s)=

my(6.0 s)=

Two circular disks spaced 0.005 m (0.50 cm) apart form a parallel-plate capacitor. Transferring 1.10 ×10^9 electrons from one disk to the other causes the electric field strength to be 2.50 ×10^5N/C. What are the diameters of the disks? Express your answer with the appropriate units.

Compare and contrast the resistors and capacitors, separately combined, in a series and parallel settings.

Or

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

Please remember to always add references and provide substantial answers. Also, respond to one other post submitted by your peer - MORE RESPONSES ARE PREFERRED . This post needs to actually discuss the submitted work by your peer. In lieu of this, you can also respond to a post submitted by your professor. But, such a response too should be an actual discussion. An actual discussion is not merely stating, “Good job,” or other similar phrases. The references should not be from sources, such as Wikipedia, yahoo.com, answers.com, etc.