PHYSICS ASSIGNMENT
Part One: Applying Coulomb's Law
1. What is the distance between two charges of - 5.00 C each if the force of electrostatic repulsion acting on them is 4.00 x 103 N?
2. Three charges are placed in a line as shown below.
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a. What is the net electrostatic force on charge A?
b. What is the net electrostatic force on charge B?
3. As shown below, an equilateral triangle with sides of 0.150 m has three charges of -2.50 microcoulombs each, situated on the vertices of the triangle. Calculate the net electrostatic force on each charge. What assumption did you have to make to complete the calculation? Reminder: Your answer must include magnitude and direction.
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Part Two: Electric Fields
1. Calculate and illustrate the electric field strength at a distance of 8.25 m from a +6.50 μC charged particle. Use the simulation to verify your field diagram. Show the direction of the field at location P in the diagram below or indicate it in your written answer.
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2. A particle has a charge of -5.00 μC. At a point near this particle, the electric field strength is 7.20 × 107 N/C. Determine the distance from this point to the charged particle.
3. Point P is collinear with a +2.80 μC charged particle and a -8.50 μC charged particle as shown in the diagram below. Point P is 10 cm to the left of the positive charge and 20 cm to the left of the negative charge. What is the electric field at point P?
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4. The diagram below shows two charged spheres arranged to the left of a point in space labelled P. Use the information on the diagram to calculate the magnitude and direction of the net electric field at point P.
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5. After reading about St. Elmo's fire, (refer to pages 555 - 558 of your physics text), answer the following questions.
a. Compare the charge distribution on a flat surface compared to a curved surface and explain why these distributions occur.
b. A metallic conductor has a fixed charge on it. How could you increase the electric field intensity on its surface without adding extra charge?
c. Under what conditions is a hot ionizing gas called a plasma formed?
d. Why can't St Elmo's fire be observed in the interior of a conductor?
Part Three: Electric Potential Energy
1. Describe the motion of a test charge in a uniform electric field.
2. Describe the motion of a test charge in a non-uniform electric field.
3. By considering the electric forces acting and Newton's second law, explain the type of motion occurring in a uniform electric field.
4. By considering the electric forces acting and Newton's second law, explain the type of motion occurring in a non-uniform electric field.
5. In which direction must a test charge be moved within an electric field if potential energy is to be stored in the system? Explain. (Consider both positive and negative charges.)
6. A student wanted to determine if the electric potential varied inversely as the square of the distance in a non-uniform field. Data collected was organized in the table below. Analyze the data and determine if the electric potential varies inversely as the square of the distance in a non-uniform field.
Distance of Test Charge from Source Charge (m)
|
Electric Potential (x 104 V)
|
100
|
27.0
|
200
|
13.5
|
300
|
8.99
|
400
|
6.74
|
500
|
5.39
|
600
|
4.49
|
7. Explain why the equation |E→| = kqsource/r2 cannot be applied in the following situations.
a. Situation one.
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b. Situation two.
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8. Determine the maximum speed an alpha particle could obtain if it moves from rest through a potential difference of 8.40 kV. Remember to show all work.