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5.5 Net And Total Distanceap Calculus

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There's a difference between how far someone travels, and the change between their starting and ending positions. Take a basketball player running suicide drills. He travels to one line and back to his starting point, then to a farther line and back to his starting point, and does that several times. By the time he's done, he's certainly travelled some distance. However, since he ends up back where he started, his change in position is 0.

Total

5.5 Net And Total Distanceap Calculus Formula

When we integrate a velocity function from t = a to t = b, the number we get is the change in position between t = a and t = b. If we want to know the total distance travelled, we have to do something different. We don't want travel in opposite directions canceling out, so we find how far we travel in one direction

Total displacement. Displacement = To find the distance traveled we have to use absolute value. Distance traveled = To find the distance traveled by hand you must: Find the roots of the velocity equation and integrate in pieces, just like when we found the area between a curve and x-axis. (Take the absolute value of each integral.). Calculus Notes 5.5 & 5.6: Net or Total Change as the Integral of a Rate and Substitution Method. Example 2: The number of cars per hour passing an observation point along a highway is called the traffic flow rate q(t) (in cars per hour). The flow rate is recorded at 15-minute intervals between 7:00 and 9:00 AM. The net rate of change of salt in the tank at time t? SOLUTION: Net change is given by gain minus loss, so using parts (b) and (c), dS dt g min = 24 S(t) 25 g min.5.(e). (4 points) Write an initial value problem relating S(t) and dS dt. Solve the initial value problem. SOLUTION: The initial value problem is dS dt = 24 S(t) 25, with S(0) = 800. So plus this area right over here. And so this is going to five times five times 1/2 plus five times five times 1/2, which is going to be 25 meters. The particle has gone 12.5 meters to the right, and then it goes back 12.5 meters to the left. Your displacement, your net change in position is a zero, but the total length of path traveled is 25.

and how far we travel in the opposite direction

and then, instead of subtracting, we add these distances together. We're pretending all the distances travelled are in the same direction. Another way to think of this is that we're integrating the absolute value of the velocity function, |v(t)|.

5.5 Net And Total Distanceap Calculus 14th Edition

This gets us the total (unweighted) area between the function v(t) and the horizontal axis.

Sample Problem

A cat climbs a tree with velocity given by the graph below.

If the cat starts at ground level (height s(0) = 0 feet),

(a) how high is the cat when t = 8 seconds?

(b) what is the total distance the cat travels from t = 0 to t = 8?

Answers.

Calculator

(a) This part of the question is like ones we did earlier. We want to know the cat's change in position from t = 0 to t = 8, so we integrate the velocity function by looking at the areas on the graph. We find that

5.5 net and total distanceap calculus ab

5.5 Net And Total Distanceap Calculus Formula

When we integrate a velocity function from t = a to t = b, the number we get is the change in position between t = a and t = b. If we want to know the total distance travelled, we have to do something different. We don't want travel in opposite directions canceling out, so we find how far we travel in one direction

Total displacement. Displacement = To find the distance traveled we have to use absolute value. Distance traveled = To find the distance traveled by hand you must: Find the roots of the velocity equation and integrate in pieces, just like when we found the area between a curve and x-axis. (Take the absolute value of each integral.). Calculus Notes 5.5 & 5.6: Net or Total Change as the Integral of a Rate and Substitution Method. Example 2: The number of cars per hour passing an observation point along a highway is called the traffic flow rate q(t) (in cars per hour). The flow rate is recorded at 15-minute intervals between 7:00 and 9:00 AM. The net rate of change of salt in the tank at time t? SOLUTION: Net change is given by gain minus loss, so using parts (b) and (c), dS dt g min = 24 S(t) 25 g min.5.(e). (4 points) Write an initial value problem relating S(t) and dS dt. Solve the initial value problem. SOLUTION: The initial value problem is dS dt = 24 S(t) 25, with S(0) = 800. So plus this area right over here. And so this is going to five times five times 1/2 plus five times five times 1/2, which is going to be 25 meters. The particle has gone 12.5 meters to the right, and then it goes back 12.5 meters to the left. Your displacement, your net change in position is a zero, but the total length of path traveled is 25.

and how far we travel in the opposite direction

and then, instead of subtracting, we add these distances together. We're pretending all the distances travelled are in the same direction. Another way to think of this is that we're integrating the absolute value of the velocity function, |v(t)|.

5.5 Net And Total Distanceap Calculus 14th Edition

This gets us the total (unweighted) area between the function v(t) and the horizontal axis.

Sample Problem

A cat climbs a tree with velocity given by the graph below.

If the cat starts at ground level (height s(0) = 0 feet),

(a) how high is the cat when t = 8 seconds?

(b) what is the total distance the cat travels from t = 0 to t = 8?

Answers.

(a) This part of the question is like ones we did earlier. We want to know the cat's change in position from t = 0 to t = 8, so we integrate the velocity function by looking at the areas on the graph. We find that

5.5 Net And Total Distanceap Calculus Ab

so the cat's position at t = 8 is s(8) = 12 feet.

(b) This part of the question is asking for the total distance the cat traveled, which means we want to find .

To do this we count all the areas between the graph of v(t) and the horizontal axis positively, to get

5.5 Net And Total Distanceap Calculus Calculator

This means the cat traveled a total distance of 18 feet.





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