Calculus 1 : Spatial Calculus

Study concepts, example questions & explanations for Calculus 1

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Example Questions

Example Question #611 : Spatial Calculus

A driver is speeding through the interstate.  The distance traveled by the driver over a certain amount of time can be calculated by the equation

\displaystyle x(t) = 20\frac{m}{s^{2}} (t^{2}) + 10m

where \displaystyle x is the distance traveled in \displaystyle meters and \displaystyle t is time in \displaystyle seconds.

What is the equation for the acceleration of the driver? 

Possible Answers:

\displaystyle a(t) = 20\tfrac{m}{s} (t)

\displaystyle a(t) = 20\tfrac{m}{s} (t^{2})

\displaystyle a(t) = 20\tfrac{m}{s^{2}}

\displaystyle a(t) = 2\tfrac{m}{s^{2}}

\displaystyle a(t) = 40\tfrac{m}{s} (t)

Correct answer:

\displaystyle a(t) = 20\tfrac{m}{s^{2}}

Explanation:

To find the velocity of the driver, we take the derivative of the position equation. The velocity equation is

\displaystyle v(t) = 20\tfrac{m}{s} (t)

Then to find the acceleration of the toy car, we take the derivative again.  The acceleration equation is 

\displaystyle a(t) = 20\tfrac{m}{s}

Example Question #221 : How To Find Acceleration

A driver is speeding through the interstate.  The distance traveled by the driver over a certain amount of time can be calculated by the equation

\displaystyle x(t) = 20\frac{m}{s^{2}} (t^{2}) + 10m

where \displaystyle x is the distance traveled in meters and \displaystyle t is time in \displaystyle seconds.

What is the instantaneous acceleration of the driver at any time?

Possible Answers:

\displaystyle 10\tfrac{m}{s^{2}}

\displaystyle 20\tfrac{m}{s^{2}}

\displaystyle 30\tfrac{m}{s^{2}}

\displaystyle 40\tfrac{m}{s^{2}}

\displaystyle 2\tfrac{m}{s^{2}}

Correct answer:

\displaystyle 20\tfrac{m}{s^{2}}

Explanation:

To find the velocity of the driver, we take the derivative of the position equation. The velocity equation is

\displaystyle v(t) = 20\tfrac{m}{s} (t)

Then to find the acceleration of the toy car, we take the derivative again.  The acceleration equation is 

\displaystyle a(t) = 20\tfrac{m}{s}

Example Question #222 : How To Find Acceleration

What is the acceleration of an object following the path of \displaystyle y=e^tsin(t) at \displaystyle t=2\pi

Possible Answers:

\displaystyle 2e^{2\pi}

\displaystyle -2e^{2\pi}

\displaystyle e^{2\pi}

\displaystyle 0

Correct answer:

\displaystyle 2e^{2\pi}

Explanation:

Remember that acceleration is the second derivative of position with respect to time. 

By the product rule, we know that

\displaystyle \frac{d}{dt}(f(t)*g(t))=f'(t)*g(t)+g'(t)f(t), where \displaystyle f and \displaystyle g are functions that have first derivatives \displaystyle f' and \displaystyle g'

Keeping this in mind:

\displaystyle y(t)=e^tsin(t)

\displaystyle y'(t)=e^tsin(t)+e^tcos(t)

To solve for the second derivative, we have to take the product rule for each term:

\displaystyle y''(t)=e^tsin(t)+e^tcos(t)+e^tcos(t)-e^tsin(t)

            \displaystyle =2e^tcos(t)

Solving for \displaystyle y''(2\pi),

\displaystyle y''(2\pi)=2e^{2\pi}cos({2\pi})=2e^{2\pi}

 

Example Question #223 : How To Find Acceleration

You are given the position function:

 \displaystyle X(t) = 6t^2 + 2t -5

Find the acceleration \displaystyle a(t) at time \displaystyle 2.

Possible Answers:

\displaystyle a(2) = -5

\displaystyle a(2) = 24

\displaystyle a(2) = 14

\displaystyle a(2) = 12

\displaystyle a(2) = 0

Correct answer:

\displaystyle a(2) = 12

Explanation:

The acceleration function is given by the second derivative of the position function. Take the first derivative of \displaystyle X(t) using the power rule:

\displaystyle \frac{\mathrm{d} }{\mathrm{d} x} x^n = nx^{n-1}

Applying the power rule to this equation, noting the constant of \displaystyle 6 in the first term:

\displaystyle \frac{dX}{dt} X(t) = 12t + 2

This is the velocity function. Take the derivative once again to find the acceleration.

\displaystyle \frac{d^2X}{dt^2} X(t) = 12

Because there is no factor of t in the acceleration equation, you do not need to plug in \displaystyle 2 to solve for \displaystyle a(2). The acceleration is a constant \displaystyle 12.

Example Question #224 : How To Find Acceleration

Given the position function:

\displaystyle s(t)=3t^5-4t^2+8

What is the instantaneous acceleration at time (t=2 seconds)?

Possible Answers:

\displaystyle 52

\displaystyle 472

\displaystyle 88

\displaystyle 224

\displaystyle 488

Correct answer:

\displaystyle 472

Explanation:

The acceleration is simply the second derivative of the position function:

\displaystyle a(t)=s''(t)

To find the derivatives in this particular problem use the power rule which states,

\displaystyle \frac{d}{dx}x^n=nx^{n-1}

Applying the power rule once, the first derivative of the given function gives us the velocity:

\displaystyle v(t)=s'(t)=15t^4-8t

Applying the power rule a second time, the derivative of this will give us our acceleration function:

\displaystyle a(t)=60t^4-8

At time (t=2 seconds):

\displaystyle a(2)=60(2)^3-8=60(8)-8=480-8=472

This is one of the answer choices.

Example Question #225 : Acceleration

Given the position function:

\displaystyle s(t)=4t^3-5t^2+5t-100

What is the instantaneous acceleration at time (t=2 seconds)?

Possible Answers:

\displaystyle 38

\displaystyle 33

\displaystyle -78

\displaystyle 22

\displaystyle 48

Correct answer:

\displaystyle 38

Explanation:

The acceleration can be found by taking the second derivative of the position function.

To find the derivatives in this particular problem use the power rule which states,

\displaystyle \frac{d}{dx}x^n=nx^{n-1}

\displaystyle a(t)=s''(t)=\frac{d^2}{dt^2}[4t^3-5t^2+5t-100]=\frac{d}{dt}[12t^2-10t+5]=24t-10

At time (t=2 seconds):

\displaystyle a(2)=24(2)-10=48-10=38

This is one of the answer choices.

Example Question #226 : Acceleration

Given the velocity function:

\displaystyle v(t)=3t^2-9t+14

Find the instantaneous acceleration at time (t=5 seconds)

Possible Answers:

\displaystyle -27

\displaystyle -6

\displaystyle 21

\displaystyle 44

\displaystyle 6

Correct answer:

\displaystyle 21

Explanation:

The instantaneous acceleration can be found by taking the derivative of the velocity function, which is given:

To find the derivatives in this particular problem use the power rule which states,

\displaystyle \frac{d}{dx}x^n=nx^{n-1}

\displaystyle a(t)=v'(t)=\frac{d}{dt}[3t^2-9t+14]=6t-9

At time (t=5 seconds):

\displaystyle a(5)=6(5)-9=30-9=21

This is one of the answer choices.

Example Question #221 : How To Find Acceleration

Find the acceleration function if the velocity function is 

\displaystyle v(t)=et.

Possible Answers:

\displaystyle a(t)=e+t

\displaystyle a(t)=e

\displaystyle a(t)=t

\displaystyle a(t)=e+1

Correct answer:

\displaystyle a(t)=e

Explanation:

In order to find the acceleration function from the position function we need to take the derivative of the position function

\displaystyle a(t)=\frac{d}{dt}[v(t)].

When taking the derivative, we will use the power rule which states

\displaystyle \frac{\mathrm{d} }{\mathrm{d} x} x^n=nx^{n-1}

and by applying this to the given function

\displaystyle a(t)=\frac{d}{dt}[et]=1*et^{1-1}=e.

Hence

\displaystyle a(t)=e.

Example Question #222 : How To Find Acceleration

Find the acceleration function if the velocity function is 

\displaystyle v(t)=e^2.

Possible Answers:

\displaystyle a(t)=1

\displaystyle a(t)=e

\displaystyle a(t)=0

\displaystyle a(t)=e^2

Correct answer:

\displaystyle a(t)=0

Explanation:

In order to find the acceleration function from the position function we need to take the derivative of the position function

\displaystyle a(t)=\frac{d}{dt}[v(t)].

When taking the derivative, we will use the power rule which states

\displaystyle \frac{\mathrm{d} }{\mathrm{d} x} x^n=nx^{n-1}

and by applying this to the given function

\displaystyle a(t)=\frac{d}{dt}[e^2]=0.

Hence

\displaystyle a(t)=0.

Example Question #223 : How To Find Acceleration

If the velocity of an asteroid is given by \displaystyle g(x), find the function which models the acceleration of the asteroid.

\displaystyle g(x)=5sin(x)

Possible Answers:

\displaystyle 5cosx

\displaystyle cos(5x)

\displaystyle -5cosx

\displaystyle -5sin(x)

Correct answer:

\displaystyle 5cosx

Explanation:

If the velocity of an asteroid is given by g(x), find the function which models the acceleration of the asteroid.

\displaystyle g(x)=5sin(x)

Recall that a velocity function is the first derivative of a position function, and that an acceleration function is the first derivative of a velocity function.

So, to find the acceleration function, we need to find the derivative of g(x)

Begin by recalling or looking up the rule for derivative of sine:

\displaystyle \frac{d}{dx}sinx=cosx

So the answer to our question can be found via:

\displaystyle \frac{d}{dx}5sinx=5cosx

To be clear, our answer is:

\displaystyle g'(x)=5cosx

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