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If a train traveled at 50 meters within 120 seconds, what is its speed?

Alja [10]

Answer:

v = 0.416 m/s

Step-by-step explanation:

Give that,

Distance covered by a train, d = 50 m

Time taken, t = 120 s

We need to find the speed of a train. The formula for speed of an object is equal to the total distance covered divided by total time taken. It can be given by :

$v=\dfrac{d}{t}\\\\v=\dfrac{50\ m}{120\ s}\\\\v=0.416\ m/s$

So, the speed of a train is 0.416 m/s.

3 0

2 years ago

Determine whether the given vectors are orthogonal, parallel, or neither. (a) a = 9, 6 , b = −4, 6 orthogonal parallel neither (

labwork [276]

Answer:

(a) Orthogonal, (b) Neither, (c) Parallel, d( Orthogonal

Step-by-step explanation:

a and b are parallel is a=kb

a and b if a dot b = 0

(a) a dot b = (9)(-4)+6(6)=-36+36=0

a and b are orthogonal

(b) a dot b = 40-7-21=12

a=kb -> there is no k value satisfying the equation

a and b are neither parallel or orthogonal

(c) a dot b = -12-108-48=-168

a=kb -> k=-3/4 satisfies the equation

a and b are parallel

(d) a dot b= 9-3-6=0

a and b are orthogonal

5 0

3 years ago

The rate of growth of profit (in millions) from an invention is approximated by Upper P prime (x )equals x e Superscript negati

Alecsey [184]

Answer:

The function is $P(x) = \frac{1}{2} e^{-x^2} +0.016$

Step-by-step explanation:

From the question we are told that

The rate of growth is $P'(x) = xe^{x} - x^2$

The total profit is $P(2) =$ $25,000

The time taken to make the profit is $x = 2 \ years$

From the question

$P'(x) = xe^{-x^2}$ is the rate of growth

Now here x represent the time taken

Now the total profit is mathematically represented as

$P(x) = \int\limits {P'(x)} \, = \int\limits {xe^{-x^2}} \,$

So using substitution method

We have that

$u = - x^2$

$du = 2xdx$

So

$p(x) = \int\limits {\frac{1}{2} e^{-u}} \, du$

$p(x) = {\frac{1}{2} [ e^{-u}} +c ]$

$p(x) = {\frac{1}{2} e^{-x^2}} + \frac{1}{2} c$ recall $u = - x^2$ and let $\frac{1}{2} c = Z$

At x = 2 years

$P(x) =$ $25,000

So

Since the profit rate is in million

$P(x) =$ $25,000 = $\frac{25000}{1000000} =$ $0.025 millon dollars

So

$0.025 = {\frac{1}{2} e^{-2^2}} + Z$

=> $Z = 0.025 - {\frac{1}{2} e^{-2^2}}$

$Z = 0.016$

So the profit function becomes

$P(x) = \frac{1}{2} e^{-x^2} +0.016$

5 0

3 years ago

Lin runs 5 laps around a track in 8 minutes.

andrezito [222]

Answer:

To run one lap Lin takes 1.6 minutes.

Step-by-step explanation:

To find this answer you would do 8 divided by 5. Always remember when dividing time goes first unless the instructions / directions / your teacher says differently. So, when you do 8 divided by 5 the answer you get is 1.6, and there is your answer. Also to check your answer you can do 1.6 times 5, and you get 8, so you know that 1.6 is the correct answer.

5 0

3 years ago

Which one is it and why? Please actual answers only

Andrej [43]

Answer:

The first answer, 3(pi) km^2

Step-by-step explanation:

3 x pi squared determines the area

7 0

3 years ago

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