How to find distance - AP Calculus AB

Card 0 of 1652

Question

What is the midpoint of the line segment between the two points and ?

Answer

The midpoint is the average of the coordinates.

Therefore, to find the midpoint, we must add each coordinate of the first point to each coordinate of the second point and divide by two, finding the halfway point between the two points.

Compare your answer with the correct one above

Question

A boat has a velocity defined by the equation . How much distance does it cover between and ?

Answer

In order to find the distance travelled between and , we need to take the definite integral of the velocity .

Let's first define the definite integral as

for a continuous function over a closed interval with an antiderivative .

Using the inverse of the power rule

with a constant and , we can therefore determine that

Completing the integral:

.

Compare your answer with the correct one above

Question

A ship flies for a period having an acceleration of . If the ship had an initial velocy of , how far did the ship travel during the last fifteen seconds of this period?

Answer

Based on our data, we know that the equation for the acceleration of the ship is:

Now, we know that we can find the velocity of the ship by using an integral so that:

This means:

However, since we know that at time , the velocity was , must equal . Therefore, we know:

Now, the distance traveled by the ship during this period can be found by taking the definite integral from to of :

Therefore, we need to evaluate the following function for and :

Compare your answer with the correct one above

Question

The velocity of a particle is given by the function . How far does the particle travel over the interval of time ?

Answer

Velocity is the time derivative of position, and by that token position can be found by integrating a known velocity function with respect to time:

Now, if this integral were to be taken over an interval of time , this will give a finite value, a change in position, i.e. a distance travelled:

For the velocity function

The distance travelled can be found via knowledge of the following derivative properties:

Trigonometric derivative:

The distance travelled over is:

Compare your answer with the correct one above

Question

Find the distance from points: to

Answer

This is simply the application of the distance formula:

The distance is going to be equal to:

Compare your answer with the correct one above

Question

Determined the displacement of a person who walks west and north.

Answer

The displacement in orthogonal directions(North and West) can be determined by using the pythagorean theorem:

Compare your answer with the correct one above

Question

Find the midpoint of the line segment connecting the points (-1,0,5) and (3,4,1).

Answer

The coordinates of the midpoint are simply the averages of the coordinates of the two points .

(\[-1+3\]/2, \[0+4\]/2, \[5+1\]/2)

=(2/2, 4/2, 6/2)

=(1,2,3)

Compare your answer with the correct one above

Question

If the acceleration of a body at time t is given by a(t) = cos(t) + 6, what is the displacement of this particle from time t = 2 to time t = 4 if its initial velocity was 4 m / s?

Answer

To solve for this displacement, we can take the double integral of a(t). For simplicity, let us define things as follows:

v(t) = ∫(a(t) dt) and s(t) = ∫(v(t) dt)

The integrals are rather simple:

v(t) = sin(t) + 6t + c1

To solve for c1, we know that at t = 0, the initial velocity was 4. This means v(0) = sin(0) + 6 * 0 + c1 = 4; sin(0) = 0, so we know c1 = 4

Therefore, v(t) = sin(t) + 6t + 4

s(t) = –cos(t) + 3t2 + 4 * t + c2 (The final constant will drop out when we solve.)

Since we know that the body's position is always increasing (based on the initial positive velocity and an acceleration that must always be positive based on its equation), the total displacement is merely found by subtracting s(2) from s(4):

s(4) = –cos(4) + 3*42 + 16 + c2 = –cos(4) + 48 + 16 + c2 = –cos(4) + 64 + c2

s(2) = –cos(2) + 3*22 + 8 + c2 = –cos(2) + 12 + 8 + c2 = –cos(2) + 20 + c2

s(4) - s(2) = –cos(4) + 64 + cos(2) – 20 = 44.237496784317 (approx.) or 44.24

Compare your answer with the correct one above

Question

The velocity of a given particle at time t is given by the equation v(t) = 4t – 3

How far did the particle travel from time t = 4 to time t = 8?

Answer

To find the change in position, we must take the definite integral of the velocity function

\[4, 8\](4t – 3)dt = \[4, 8\](2t2 – 3t) = (2 * 82 – 3 * 8) – (2 * 42 – 3 * 4)

= 2 * 64 – 24 – (2 * 16 – 12) = 104 – 20 = 84

Compare your answer with the correct one above

Question

The velocity of an object, in meters per second, is given by the following equation:

Find the distance traveled by the object from to seconds.

Answer

To find the distance traveled by the object over a certain amount of time, we need an equation for its position. We are given an equation for its velocity, so if we integrate that equation from t=1 to t=2 seconds we'll obtain the distance traveled by the object over that interval:

Compare your answer with the correct one above

Question

Find the distance traveled by an object from to seconds if the velocity of the object, in m/s, is described by the following equation:

Answer

In order to find the distance traveled by an object we need an equation for position. If velocity is the derivative of position, then we must integrate the given equation from t=2 to t=5 to find the total distance traveled by the object over that interval:

Compare your answer with the correct one above

Question

Find the midpoint of the line segment connecting the points and .

Answer

To find the midpoint between the two points, the average of the coordinates can be taken:

Where and

Plugging in these values we find our midpoint.

Compare your answer with the correct one above

Question

If the acceleration of an object at time is given by , what is the displacement of this particle from to , if its initial velocity was .

Answer

To find the displacement of the object, we can integrate the equation for acceleration twice.

Integrating the acceleration equation once will give:

Because the initial velocity = 2, we can set . Therefore,

Therefore, .

We can now use this in the velocity equation to give

integrating the velocity equation from to will give the distance

Compare your answer with the correct one above

Question

The velocity of a particle at time is given by the equation . How far does this particle travel from to ?

Answer

To find the distance travelled, we must integrate the velocity equation

Compare your answer with the correct one above

Question

Find the distance from the first point to the second point.

First point:

Second point:

Answer

To find the distance between two points we need to find the difference of the x-coordinates and y-coordinates between the two points.

So the x-coordinate is

The y-coordinate is

So the x-coordinate and y-coordinate is

The distance can be calculated by

So plugging in

Compare your answer with the correct one above

Question

A race car is traveling at a constant 50 m/s when the driver suddenly hits the brakes. Assuming a constant deceleration of 10 m/s2, how far will the car travel before it comes to a complete stop?

Answer

To find the change in position of the car, let us start with the car's acceleration as a function of time:

Since acceleration doesn't change with time, it has a constant value.

(the negative is used to represent deceleration).

We can then integrate this function with respect to time to find velocity.

Where v0 represents the initial velocity, which was given to us as 50 m/s.

We want to know the time where the car comes to rest, meaning where v(tr) = 0.

Solving

for tr gives our time at rest, 5 s.

Now, we can integrate our velocity function with respect to time to find our position function.

Since we're not interested in the absolute position at the time of rest, but rather the change in position, we can move the x0 term to the other side of the equation:

Plugging in our values for

and

We can find how far the car travelled after the brakes were hit, our

quantity, to be .

Compare your answer with the correct one above

Question

Assume that two students are each walking on a circular path. We further suppose that these paths are centered at the origin. The radius of the first one is , and the radius of the second is . One student stopped walking and is located at . What is the distance between the two students if other one is walking on the upper half of the circle of radius ?

Answer

We will use the distance formula to show this result. Recall that having two points with coordinates , then the distance between this two points is given by:

. We will call the first fixed point . To find the second point, note that the equation of the circle with radius 1 is given by:

. Since we are looking for the upper half, we have by solving for y:

( We need only the upper half in this case , that is why y is .

Hence our second point is .

Using the distance formula we have:.

We need to simplify this expression a bit:

this gives finally after cancelling and adding:

Compare your answer with the correct one above

Question

Assume that two students are each walking on a circular path. We further suppose that these paths are centered at the origin. The radius of the first one is , and the radius of the second is . One student stopped walking and is located at . What is the distance between the two students if other one is walking on the lower half of the circle of radius ?

Answer

We will use the distance formula to show this result. Recall that having two points with coordinates , then the distance between this two points is given by:

. We will call the first fixed point . To find the second point, note that the equation of the circle with radius 1 is given by:

.

Since we are looking for the lower half, we have by solving for y:

( We need only the lower half in this case , that is why y is .

Hence our second point is .

Using the distance formula we have:.

We need to simplify this expression a bit:

this gives finally after cancelling and adding:

Compare your answer with the correct one above

Question

A person is sitting on and the other is walking on the line . What is the distance between the two?

Answer

We will use the distance formula to show this result. Recall that having two points with coordinates , then the distance between these two points is given by:

.

We will call the first fixed point .

To find the second point, note that the coordinate of the walking person is (x,4) since the x is changing and y is always 4.

Using the distance formula we have:.

We need to simplify this expression a bit:

this gives finally after cancelling and adding:

Compare your answer with the correct one above

Question

Joe is sitting on , and James is walking along the line .

What is the distance between the two ?( As a function of )

Answer

We will use the distance formula to show this result. Recall that having two points with coordinates , then the distance between these two points is given by:

.

We will call the first fixed point . To find the second point, note that the coordinates of the walking person is (x,0) since James is walking along the x-axis.

Using the distance formula we have:.

We need to simplify this expression a bit to get:

Compare your answer with the correct one above

Tap the card to reveal the answer