John Ng

The pattern we use with air resistance works on objects that are traveling on level ground, too. For example, if you stop pedaling your bicycle and just coast on a straight, level road, eventually you'll coast to a stop. The resistance here is proportiona...

5 years ago

Consider the following problem situation: At time t = 0, a country's population is 300 million, and its death rate exceeds its birth rate by k. There is also a constant immigration of I million people each year. Mathematically, this situation is similar t...

5 years ago

The differential equation for an object coasting to a stop is dv/dt = -kv, where k is constant. Claim : The equation that gives s(t) for an object coasting to a stop is s(t) = (initial v)/ k = (1- e^-kt) Here, s(t) represents the distance traveled while c...

5 years ago

A room containing 1200 cubic feet of air is originally free of carbon monoxide. Beginning at time t = 0, cigarette smoke containing 4% carbon monoxide is introduced into the room at a rate of 0.1 cubic feet per minute, and the well-circulated mixture is a...

5 years ago

At time t = 0, a country's population is 300 million, and its death rate exceeds its birth rate by k. There is also a constant immigration of (I) million people each year. Which of these differential equations describes this situation? I think its 300 e^-...

5 years ago

A dish of ice cream is left on the table in a room with a constant temperature of 70ºF. At t = 0, the temperature of the ice cream is 20ºF. Five minutes later, its temperature is 25ºF. When will it melt? (The ice cream will melt at 35ºF.) 15 minutes 16.93...

5 years ago

Let f be a polynomial function with degree greater than 2. If a ‡ b and f(a) = f(b) = 1, which of the following must be true for at least one value of x between a and b I. f(x) = 0 II. f'(x) = 0 III. f"(x) = 0 a. I only b. II only c. I and II only d. I, I...

5 years ago

At x = 3, the function given by f(x) = { x² , x<3} ; {6x-9 , x ≥ 3} is a. continuous but not differentiable. b. differentiable but not continuous. c. neither continuous nor differentiable. d. both continuous and differentiable.

5 years ago

Which of these kinds of problems is not likely to appear on the AP Exam? Finding the zero of a cubic Drawing the graph of an inverse trig function Finding the area of a region in the plane Finding the slope at a point of a curve Solving a differential equ...

5 years ago

If f(x) is continuous for all x, which of the following integrals necessarily have the same value? b I. ∫ f(x) dx a b II. ∫ |f(x)| dx a b-c III. ∫ f(x+c) dx a-c b IV. ∫ (f(x)+c) dx a I and II only I and III only I, II and IV only II, III, and IV only

5 years ago

The maximum value of f(x) = −ex + x is: 0 –1 1 In 2 Is it -1?

5 years ago

What is the minimum value of f(x) = xe^x? -1/e –e –1 0 Is it 0 or -1/e?

5 years ago

Which of the following will not give the instantaneous rate of change of f (x) with respect to x when x = 3? Which of the following will not give the instantaneous rate of change of f (x) with respect to x when x = 3? a. [f(3) - f(3 - 0.1)] / 0.1 b. lim h...

5 years ago

Physicists refer to an electron deficiency as a(n) ____. I have no clue, cant find it in my book. Beta decay or Ground State?

5 years ago

39. The electrostatic force between two charged spheres is 64 N. What will the magnitude of the force be if the size of each charge is doubled and the distance between the spheres is doubled?

5 years ago

46. A thin film of oil with a thickness of 90 nm rests on top of a pool of water. When white light incident on the film is reflected, what colors are seen? The refractive index of the oil is noil = 1.45. This is my best attempt, just wondering if I was ri...

5 years ago

48. The strongest colors reflected in a thin film have wavelengths in the film equal to ____ of the thinnest possible film. a. the thickness b. twice the thickness c. four times the thickness d. two or four times the thickness, depending upon the number o...

5 years ago

47. Induction is a process in which a moving ____ produces a(n) ____. a. charge, current c. magnetic field, electric field b. magnet, electric charge d. wave, electric field

5 years ago

25. A ____ , provided by a battery or a generator, is needed for a flow of charge to exist. A. __________ Im guessing continuous (potential difference ) in a closed loop circuit

5 years ago

2. A proton has a mass of 1.67 x 10-27 kg and a charge of 1.60 x 10-19 C. What is the weight (gravitational force) on a single proton at Earth’s surface?

5 years ago

Im thinking its a?

5 years ago