What is the frequency of a wave with the speed of 550nm/s and wavelength of 15nm

Jack and Jill exercise in a 25.0 m long swimming pool. Jack swims 9 lengths of the pool in 156.9 s ( 2 min and 36.9 s ) , wherea

Leya [2.2K]

Answer:

Jill average velocity is 0

Jack average velocity is 0.159337

Jill average speed = 1.593372

Jack average speed = 1.434034

Explanation:

given data

long swimming pool = 25.0 m

9 lengths of the pool = 156.9 s ( 2 min and 36.9 s )

10 lengths = same time interval

to find out

average velocity and average speed

solution

we know that average velocity that is express as

average velocity = $\frac{displacement}{time}$ .....................1

Jill come back where she start

so here velocity will be = 0

and

Jack ends up on the other end of pool

so average velocity = $\frac{25}{156.9}$

average velocity = 0.159337

now we get here average speed that is express as

average speed = $\frac{distance}{time}$ .............2

jack speed = 9 × $\frac{25}{156.9}$

jack speed = 1.434034

and

Jill speed = 10 × $\frac{25}{156.9}$

Jill speed = 1.593372

5 0

3 years ago

A tank is 10 m long, 6 m wide, 3 m high, and contains kerosene with density 820 kg/m3 to a depth of 2.5 m. (Use 9.8 m/s2 for the

Valentin [98]

Answer:

Explanation:

a )

Pressure on the bottom

= hdg

= 2.5 x 820 x 9.8

= 20090 N / m²

b )

force = area x pressure

= 20090 x 10 x 6 N

= 1205400 N

c )

Force on 10m x 2.5 m face

center of gravity of the tank will lie at height 2 .5 / 2 = 1.25 m

Pressure = hdg

= 1.25 x 820 x 9.8

= 10045 N/m²

force = pressure x area

= 10045 x 10 x 2.5

= 251125 N .

7 0

2 years ago

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Why does a spoon appear to be bent when it’s in a glass of water?

crimeas [40]

When light goes from one medium to another, it changes angle. This is why it will look bent.

5 0

3 years ago

Sound source A is located at x = 0, y = 0, and sound source B is located at x = 0, y = 2.3 m. The two sources radiate coherently

Oliga [24]

Answer:

Solution is given in the attachments

4 0

2 years ago

Assume that block A which has a mass of 30 kg is being pushed to the left with a force of 75 N along a frictionless surface. Wha

Veronika [31]

Answer:

The force of friction acting on block B is approximately 26.7N. Note: this result does not match any value from your multiple choice list. Please see comment at the end of this answer.

Explanation:

The acting force F=75N pushes block A into acceleration to the left. Through a kinetic friction force, block B also accelerates to the left, however, the maximum of the friction force (which is unknown) makes block B accelerate by 0.5 m/s^2 slower than the block A, hence appearing it to accelerate with 0.5 m/s^2 to the right relative to the block A.

To solve this problem, start with setting up the net force equations for both block A and B:

$F_{Anet} = m_A\cdot a_A = F - F_{fr}\\F_{Bnet} = m_B\cdot a_B = F_{fr}$

where forces acting to the left are positive and those acting to the right are negative. The friction force F_fr in the first equation is due to A acting on B and in the second equation due to B acting on A. They are opposite in direction but have the same magnitude (Newton's third law). We also know that B accelerates 0.5 slower than A:

$a_B = a_A-0.5 \frac{m}{s^2}$

Now we can solve the system of 3 equations for a_A, a_B and finally for F_fr:

$30kg\cdot a_A = 75N - F_{fr}\\24kg\cdot a_B = F_{fr}\\a_B= a_A-0.5 \frac{m}{s^2}\\\implies \\a_A=\frac{87}{54}\frac{m}{s^2},\,\,\,a_B=\frac{10}{9}\frac{m}{s^2}\\F_{fr} = 24kg \cdot \frac{10}{9}\frac{m}{s^2}=\frac{80}{3}kg\frac{m}{s^2}\approx 26.7N$

The force of friction acting on block B is approximately 26.7N.

This answer has been verified by multiple people and is correct for the provided values in your question. I recommend double-checking the text of your question for any typos and letting us know in the comments section.

6 0

3 years ago

Read 2 more answers

What is the frequency of a wave with the speed of 550nm/s and wavelength of 15nm​

What is the frequency of a wave with the speed of 550nm/s and wavelength of 15nm