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3 years ago

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A motorboat travels directly east. During its trip, winds blow from directly north, directly south, and southwest. Which of the

following statements is true? A. All of the winds do work on the boat. B. Only the north wind does work on the boat. C. Only the south wind does work on the boat. D. Only the southwest wind does work on the boat.

1 answer:

denis23 [38]3 years ago

3 0

<span>D. Only the southwest wind does work on the boat. This is because the North and South winds are opposite each other and hence cancel each other out so work is not done.</span>

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In a 50 km/h head-on crash test, the steering column of passenger car 1 moved 3 cm upward and 2 cm rearward. The steering column

Softa [21]

Answer:

Car 1

Explanation:

The steering column which moves the least is less likely to to the driver's chest ordinarily. Driver tends to remain in motion until restrained. Assuming a seat belt not airbag

Generally one would compute a vector find direction and distance. This is like solving for a hypotenuse / in a right angled triangle problem. On face value the column moving the least is safer. The 6/24 would hit the upper chest, face, or possibly break the neck.

hence, car 1 moved 3 cm upward and 2 cm rearward is safer.

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2 years ago

To practice Problem-Solving Strategy 27.1: Magnetic Forces. A particle with mass 1.81×10−3 kgkg and a charge of 1.22×10−8 CC has

Roman55 [17]

Answer:

The magnitude of the acceleration is $a = 0.33 m/s^2$

The direction is $- \r k$ i.e the negative direction of the z-axis

Explanation:

From the question we are that

The mass of the particle $m = 1.8*10^{-3} kg$

The charge on the particle is $q = 1.22*10^{-8}C$

The velocity is $\= v = (3.0*10^4 m/s ) j$

The the magnetic field is $\= B = (1.63T)\r i + (0.980T) \r j$

The charge experienced a force which is mathematically represented as

$F = q (\= v * \= B)$

Substituting value

$F = 1.22*10^{-8} (( 3*10^4 ) \r j \ \ X \ \ ( 1.63 \r i + 0.980 \r j )T)$

$= 1.22 *10^{-8} ((3*10^4 * 1.63)(\r j \ \ X \ \ \r i) + (3*10^4 * 0.980) (\r j \ \ X \ \ \r j))$

$= (-5.966*10^4 N) \r k$

Note :

$i \ \ X \ \ j = k \\\\j \ \ X \ \ k = i\\\\k \ \ X \ \ i = j\\\\j \ \ X \ \ i = -k \\\\k \ \ X \ \ j = -i\\\\i \ \ X \ \ k = - j\\$

Now force is also mathematically represented as

$F = ma$

Making a the subject

$a = \frac{F}{m}$

Substituting values

$a =\frac{(-5.966*10^4) \r k}{1.81*10^{-3}}$

$= (-0.33m/s^2)\r k$

$= 0.33m/s^2 * (- \r k)$

6 0

3 years ago

Ag,Au and Cu are called coinage metals why plzzzz hurry its urgent plzzz

Ronch [10]

Answer:

This is because these metals are used for minting (making) coins.

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3 years ago

A car travels 200km in 3.0 hours. Determine the average velocity of the car

Masja [62]

Answer:

<h2>66.67 km/hr</h2>

Explanation:

The average velocity of the car can be found by using the formula

$a = \frac{d}{t } \\$

d is the distance

t is the time taken

From the question we have

$a = \frac{200}{3} \\ = 66.66666...$

We have the final answer as

<h3>66.67 km/hr</h3>

Hope this helps you

4 0

3 years ago

The average lifetime of μ-mesons with a speed of 0.95c is measured to be 6 x 10^6 s. Find the average lifetime of μ-mesons in a

Mnenie [13.5K]

Answer:

19.2*10^6 s

Explanation:

The equation for time dilation is:

$t = \frac{t'}{\sqrt{1-\frac{v^2}{c^2}}}$

Then, if it is observed to have a life of 6*10^6 s, and it travels at 0.95 c:

$t = \frac{6*10^6}{\sqrt{1-\frac{(0.95c)^2}{c^2}}} = 19.2*10^6 s$

It has a lifetime of 19.2*10^6 s when observed from a frame of reference in which the particle is at rest.

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3 years ago