Calculus 1 : How to find acceleration

Study concepts, example questions & explanations for Calculus 1

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Example Questions

Example Question #501 : Calculus

An apple rolls off of a table. It's position is given by the following: \displaystyle s(t)=-4t^2+8t+16

What is the acceleration of the apple?

Possible Answers:

\displaystyle -8m/s^2

\displaystyle -16m/s^2

\displaystyle 8m/s^2

\displaystyle 0m/s^2

Correct answer:

\displaystyle -8m/s^2

Explanation:

Take the second derivative of \displaystyle s(t) by using the Power Rule \displaystyle x^n=nx^{n-1} twice .

Applying the power rule once will give us our velocity function,

 \displaystyle s'(t)=-8t+8.

Applying the power rule a second time results in our acceleration function,

\displaystyle s''(t)=-8.

Therefore, the acceleration of the apple is \displaystyle -8m/s^2.

Example Question #502 : Calculus

A boulder rolls into a valley. Its position is given by \displaystyle s(t)=5t^2-10t+25, where \displaystyle s represents distance in yards and \displaystyle t represents time in seconds.

What is the acceleration of the boulder at \displaystyle t=4?

Possible Answers:

\displaystyle 10yd/s

\displaystyle 5yd/s

\displaystyle 20yd/s

\displaystyle 2yd/s

Correct answer:

\displaystyle 10yd/s

Explanation:

Take the second derivative by using the Power Rule \displaystyle x^n=nx^{n-1} of \displaystyle s(t),

\displaystyle \\s'(t)=v(t)\\ v(t)=5(2)t-10\\v(t)=10t-10.

Applying the power rule a second time we find the acceleration function,

\displaystyle s''(t)=10.

Example Question #503 : Calculus

Lola tosses an acorn into the lake. The position of the acorn is represented by \displaystyle s(t)=-3t^2+5t-4, where \displaystyle s represents distance in feet and \displaystyle t represents time in seconds. 

What is the acceleration of the acorn?

Possible Answers:

\displaystyle -3ft/s

\displaystyle -6ft/s

\displaystyle 3ft/s

\displaystyle 6ft/s

Correct answer:

\displaystyle -6ft/s

Explanation:

Take the second derivative by using the Power Rule \displaystyle x^n=nx^{n-1} of \displaystyle s(t),

\displaystyle \\s'(t)=-3(2)t+5\\s'(t)=-6t+5.

Applying the power rule again we find our acceleration function,

\displaystyle \\s''(t)=a(t)\\s''(t)=-6.

Example Question #505 : Spatial Calculus

Sian tosses an apple into the air. Its position is represented by \displaystyle s(t)=-4t^2+12t-12, where \displaystyle s represents distance in feet and \displaystyle t represents time in seconds.

What is the acceleration of the apple?

Possible Answers:

\displaystyle -8ft/s

\displaystyle 12ft/s

\displaystyle -16ft/s

\displaystyle 4ft/s

Correct answer:

\displaystyle -8ft/s

Explanation:

Take the second derivative by using the Power Rule \displaystyle x^n=nx^{n-1} of \displaystyle s(t),

\displaystyle s'(t)=-4(2)t+12.

Applying the power rule again we get the acceleration function,

\displaystyle \\s''(t)=a(t)\\a(t)=-8.

Example Question #504 : Calculus

Piper throws a softball. Its position is represented by \displaystyle s(t)=-8t^2+20t-12, where \displaystyle s represents distance in meters and \displaystyle t represents time in seconds.

What is the acceleration of the softball?

Possible Answers:

\displaystyle 20m/s

\displaystyle -8m/s

\displaystyle -16m/s

\displaystyle 4m/s

Correct answer:

\displaystyle -16m/s

Explanation:

Take the second derivative by using the Power Rule \displaystyle x^n=nx^{n-1} of \displaystyle s(t),

\displaystyle s'(t)=-8(2)t+20.

Applying the power rule a second time we find the acceleration function,

\displaystyle \\s''(t)=a(t)\\a(t)=-16.

Example Question #112 : How To Find Acceleration

Find the acceleration function 

\displaystyle a(t)

if

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

Possible Answers:

\displaystyle a(t)=6t

\displaystyle a(t)=16t

\displaystyle a(t)=6t+10

\displaystyle a(t)=3t^2+10t+2

Correct answer:

\displaystyle a(t)=6t+10

Explanation:

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

\displaystyle a(t)=\frac{d^2}{dt^2}[s(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 rule to each term we get

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

\displaystyle =\frac{d^2}{dt^2}[t^3+5t^2+2t+4]

\displaystyle =\frac{d}{dt}[3t^{3-1}+2\cdot 5t^{2-1}+2t^{1-1}+0]

\displaystyle =\frac{d}{dt}[3t^2+10t+2].

Next we find the second derivative,
\displaystyle a(t)=\frac{d}{dt}[3t^2+10t+2]

\displaystyle =2\cdot 3t^{2-1}+10t^{1-1}+0

\displaystyle =6t+10.

Hence,

\displaystyle a(t)=6t+10.

Example Question #505 : Calculus

Find \displaystyle a(4) if

\displaystyle v(t)=5t^2 +3.

Possible Answers:

\displaystyle 23

\displaystyle 40

\displaystyle 20

\displaystyle 43

Correct answer:

\displaystyle 40

Explanation:

In order to find the acceleration function from the velocity function we need to take the derivative of the velocity 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 rule to each term we get

\displaystyle \frac{d}{dt}[v(t)]=\frac{d}{dt}[5t^2+3]=2\cdot 5t^{2-1}+0.

As such, 

\displaystyle a(t)=10t.

Finally, to solve for \displaystyle a(4) we set \displaystyle t=4 to get

\displaystyle a(4)=40.

Example Question #509 : Spatial Calculus

A particle is moving according to the following equation:

\displaystyle f(x)=2x^2+3x+1

What is the acceleration of the particle at the point \displaystyle (2,15)?

Possible Answers:

\displaystyle 2

\displaystyle 15

\displaystyle 8

\displaystyle 4

Correct answer:

\displaystyle 4

Explanation:

The position function of the particle is given as follows:

\displaystyle f(x)=2x^2+3x+1

The first derivative of the position function describes the velocity of the particle:

\displaystyle f'(x)=4x+3
This derivative was found by using the power rule \displaystyle \frac{d}{dx}x^n=nx^{n-1}, the derivative of x=1, and the derivative of a constant equaling zero.

The second derivative of the function - the derivative of the first derivative of the position function - describes the acceleration of the particle:

\displaystyle f''(x)=4

The derivative was found by the derivative of x=1, and the derivative of the constant equaling zero.

Thus, the acceleration of the particle is 4.

Example Question #112 : How To Find Acceleration

A spaceship is traveling from Venus to Mercury according to the following equation:

\displaystyle s(t)=4t^4+28t^2+9

Find the acceleration of the spaceship at \displaystyle t=10.

Possible Answers:

\displaystyle 16560

None of the other answers

\displaystyle 545

\displaystyle 4856

Correct answer:

\displaystyle 4856

Explanation:

The acceleration of the spaceship is given by the second derivative of the position equation.

The first derivative - which describes the velocity of the spaceship - is given by 

\displaystyle v(t)=16t^3+56t.

This derivative was found using the power rule This derivative was found by using the power rule 

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

The derivative of this function (the second derivative of the initial function)- the acceleration of the spaceship - is given by 

\displaystyle a(t)=48t^2+56.

This derivative was also found using the power rule, and the rule that the derivative of a constant (in this case, 56) equals zero.

At \displaystyle t=10, the acceleration 

\displaystyle a(10)=48(10)^2+56

\displaystyle a(10)=4856.

Example Question #111 : How To Find Acceleration

A paper airplane flies across a room. It's position is represented by \displaystyle s(t)=-14t^2+6t+20, where \displaystyle s represents distance in feet and \displaystyle t represents time in seconds.

What is the acceleration of the airplane?

Possible Answers:

\displaystyle -12\frac{ft}{s^2}

\displaystyle -28\frac{ft}{s^2}

\displaystyle 20\frac{ft}{s^2}

\displaystyle -14\frac{ft}{s^2}

Correct answer:

\displaystyle -28\frac{ft}{s^2}

Explanation:

Take the first derivative by using the Power Rule (\displaystyle x^n=nx^{n-1}) of \displaystyle s(t):

\displaystyle s'(t)=-28t+6

Using the Power Rule again, find the second derivative of \displaystyle s(t):

\displaystyle s''(t)=-28

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