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2 years ago

A hockey puck sliding at 60.0m/s slows uniformly to 20.0m/s while travelling 800.0m.

1 answer:

3 0

A) -3.75 meters/second
A=(20^2-80^2)/(2x800)
=(400-6400)/1600
=-6000/1600
=-3.75
B) 16 seconds
t=(20-80)/-3.75
=-60/-3.75
=16

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) is it possible for one component of a vector to be zero, while the vector itself is not zero?

Natalka [10]

The least number of component of a vector quantity is two. These are the x-component and the y-component.

The resultant vector, or vector as we refer to it in this item, can be calculated through the equation,
RV = sqrt ((Vx)² + (Vy)²)

From the equation, it can be noted that if we let Vx equal to zero,
RV = Vy

Similarly, if we let Vy be equal to zero then,
RV = Vx

Thus, it is still possible for the vector to become nonzero even if one of its components is zero.

8 0

3 years ago

A soccer player kicks a rock horizontally off a 37 m high cliff into a pool of water. If the player hears the sound of the splas

Alchen [17]

<h2>Answer:</h2>

(a). 16.741 m/s

(b). 15.75 m/s

<h2>Explanation:</h2>

In the question,

Height of the cliff, h = 37 m

Time taken to reach the sound to us = 2.92 s

Speed of the sound in air at room temperature = 343 m/s

Now,

Let us say the speed of the ball = u m/s

So,

Time taken by the ball to reach at the bottom, t is given by,

$t=\sqrt{\frac{2h}{g}}\\t=\sqrt{\frac{2\times 37}{9.8}}\\t=2.747\,s$

So,

Splash is heard after = 2.92 s

So,

Time taken by sound to travel the shortest distance along the hypotenuse of the triangle thus formed is,

t = 2.92 - 2.747

t = 0.172 s

Now,

Distance traveled by sound is given by,

$Distance=343\times 0.172\\Distance=59.02\,m$

So,

In the triangle using the Pythagoras Theorem,

Horizontal distance traveled is,

$D=\sqrt{59.02^{2}-37^{2}}\\D=45.99\,m$

So,

Speed of throwing of ball is given by,

$Distance=Speed\times Time\\45.99=u\times 2.747\\u=16.741\,m/s$

Therefore, the speed of the ball = 16.741 m/s.

(b).

If,

Speed of sound = 331 m/s

So,

Distance traveled by sound is,

$Distance=331\times 0.172\\Distance=56.932\,m$

So,

Distance traveled in the horizontal by ball is,

$Distance=\sqrt{56.932^{2}-37^{2}}\\Distance=43.269\,m$

So,

Speed of the ball thrown is given by,

$Speed=\frac{Distance}{Time}\\Speed=\frac{43.269}{2.747}\\Speed=15.75\,m/s$

Therefore, the speed of the ball = 15.75 m/s.

8 0

3 years ago

We know the frequency range of certain sounds are: 400-560 Hz, what are the ranges of wavelength in meters when the signal trans

Ksivusya [100]

Answer:

Range of wavelength will be $5.35\times 10^5m$ to $7.5\times 10^5m$

Explanation:

We have given range of frequency is 400-560 Hz

Speed of the light $c=3\times 10^8m/sec$

We have to find the range of the wavelength of signal transmitted

Ween know that velocity is given by $v=\lambda f$ , here $\lambda$ is wavelength and f is frequency

So for 400 Hz frequency wavelength will be $\lambda =\frac{c}{f}=\frac{3\times 10^8}{400}=7.5\times 10^5m$

And wavelength for frequency 560 Hz $\lambda =\frac{c}{f}=\frac{3\times 10^8}{560}=5.35\times 10^5m$

So range of wavelength will be $5.35\times 10^5m$ to $7.5\times 10^5m$

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3 years ago

Which one of the following statements about sulfuric acid is correct?

kherson [118]

The answer is C. Sulfuric Acid is dangerous to living organism

Direct contact with your skin and it will cause Chemical Burns , Direct contact with your eyes and it could cause a permanent Blindness.

This chemical also suck the water out of everything, so you can guess what will happen if it get into your body.

6 0

2 years ago

The woman in the first photo lifts a plant 2 m

Serjik [45]

Answer:

65x2=130

that's what she does

8 0

3 years ago