An electric field is applied to a solution containing bromide ions. As a result, the ions move through the solution with an average drift speed of $3.7 \times 10^{-7}\ \mathrm{m} / \mathrm{s}.$ The mobility of bromide ions in solution is $8.1 \times 10^{-8}\ (\mathrm{m} / \mathrm{s}) /(\mathrm{N} / \mathrm{C}) .$ What is the magnitude of the net electric field inside the solution?

a. What are some regular services that are provided by community volunteers? b. Do you think is it important for citizens to volunteer their services in their communities? Why or why not?

The mobility of $\mathrm{Na}^{+}$ ions in water is $5.2 \times 10^{-8}\ (\mathrm{m} / \mathrm{s}) /(\mathrm{N} / \mathrm{C}).$ If an electric field of 2400 N/C is maintained in the fluid, what is the drift speed of the sodium ions?

You place a neutral block of nickel near a small glass sphere that has a charge of $2 \times 10^{-8}$ C uniformly distributed over its surface. About how long do you have to wait to make sure that the mobile electron sea inside the nickel block has reached equilibrium? (1) Less than a nanosecond $\left(1 \times 10^{-9} \mathrm{s}\right),$ (2) Several hours, (3) About 1 s, (4) About 10 min.

An electron and a neutral carbon atom are initially $1 \times 10^{-6} \mathrm{m}$ apart (about 10000 atomic diameters), and there are no other particles in the vicinity. The polarizability of a carbon atom has been measured to be $\alpha=1.96 \times 10^{-40} \mathrm{C} \cdot \mathrm{m} /(\mathrm{N} / \mathrm{C}).$ Calculate the initial magnitude and direction of the acceleration of the electron. Explain your steps clearly. Pay particular attention to clearly defining your algebraic symbols. Don't put numbers into your calculation until the very end.

In general, what happens to the reactivity of elements in groups labeled A as atomic numbers increase across a period?

Find

$$\int\left[\left(x^{2}-1\right)(x+1)\right]^{-2 / 3} d x$$

Two dice are rolled, one blue and one red. How many outcomes have neither die showing 2?

An electric field of magnitude 190 N/C is applied to a solution containing chloride ions. The mobility of chloride ions in solution is $7.91 \times 10^{-8}(\mathrm{m} / \mathrm{s}) /(\mathrm{N} / \mathrm{C}).$ What is the average drift speed of the chloride ions in the solution?

You observe that a negatively charged plastic pen repels a charged piece of invisible tape. You then observe that the same piece of tape is repelled when brought near a metal sphere. You are wearing rubber-soled shoes, and you touch the metal sphere with your hand. After you touch the metal sphere, you observe that the tape is attracted to the metal sphere. Which of the following statements could be true? Check all that apply. (1) Electrons from the sphere traveled through your body into the Earth. (2) Electrons from the sphere moved into the salt water on your skin, where they reacted with sodium ions. (3) After you touched it, the metal sphere was very nearly neutral. (4) Chloride ions from the salt water on your hand moved onto the sphere. (5) The excess negative charge from the sphere spread out all over your body. (6) Electrons from your hand moved onto the sphere. (7) Sodium ions from the salt water on your hand moved onto the sphere.

Solve:

$$\frac { 1 } { x + 2 } = \frac { 4 } { x ^ { 2 } - 4 } - \frac { 1 } { x - 2 }.$$

An electron and a neutral carbon atom are initially $1 \times 10^{-6} \mathrm{m}$ apart (about 10000 atomic diameters), and there are no other particles in the vicinity. The polarizability of a carbon atom has been measured to be $\alpha=1.96 \times 10^{-40} \mathrm{C} \cdot \mathrm{m} /(\mathrm{N} / \mathrm{C}).$ If the electron and carbon atom were initially twice as far apart, how much smaller would the initial acceleration of the electron be?

Write True if the statement is true. If the statement is false, change the underlined word or words to make the statement true. In a slime mold's life cycle, germinating spores release amoeba-like cells.

Find the exact value of s in the given interval that has the given circular function value. Do not use a calculator. $\left[\frac{3 \pi}{2}, 2 \pi\right]$; $\cos s=\frac{\sqrt{3}}{2}$