1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Oliga [24]
2 years ago
15

A gauge is reading the pressure at the bottom of a river, at a depth of 6 m. Would the reading be greater or smaller than the re

ading at the bottom of a lake at the same depth? You must provide a clear explanation for full credit.
Physics
1 answer:
Alex787 [66]2 years ago
5 0

Answer:

The pressure at the bottom of the river is less than that at the bottom of the lake.

Explanation:

From Bernoulli's equation, the pressure difference is given by

ΔP = ρgΔh + ρ(v₂² - v₁²)/2 where ρ = density of water, g = acceleration due to gravity, Δh = depth, v₁ = velocity at top, v₂ = velocity at bottom

For the lake, v₁ = v₂, since the velocity at the top and bottom are the same. So,

ΔP₁ = ρgΔh + ρ(v₁² - v₁²)/2 = ρgΔh + 0 = ρgΔh

P₂ - P₁ = ρgΔh

P₂ = P₁ + ρgΔh

For the river, v₁ < v₂, since the velocity at the top of the river is greater than at the bottom.

So,

ΔP₂ = ρgΔh + ρ(v₂² - v₁²)/2.

Since  v₁ < v₂, ρ(v₂² - v₁²)/2 will be negative,

So,

ΔP₂ = ρgΔh - ρ(v₂² - v₁²)/2.

Since ρ(v₂² - v₁²)/2 is negative, making ΔP less than that in the lake.

So, ΔP₂ = ΔP₁ -  ρ(v₂² - v₁²)/2.

ΔP₂ = P₃ - P₁

P₃ - P₁ = P₂ - P₁ -  ρ(v₂² - v₁²)/2.

P₃ = P₂ - ρ(v₂² - v₁²)/2.

where P₃ = pressure at bottom of the river and P₂ = pressure at bottom of the lake and P₁ = atmospheric pressure at top of river and lake respectively.

Since the factor ρ(v₂² - v₁²)/2 is removed from the pressure at the bottom of the lake, the pressure at the bottom of the river is therefore less than that at the bottom of the lake.

You might be interested in
Help with 7,8,9 please!!
Marysya12 [62]

# 7 the answer is 4) because you need opposites in order to attract

# 8 I'm going to guess it is 4) because electricity is needed in order a light bolt to work.(don't take my word for this one I'm not sure but, the other answer are correct)

# 9  the answer is 4) because the comb dose collect negative charges from the hair in order to make the hair have positive charge.


Hope this helped : )

4 0
2 years ago
The Sun's surface temperature is closest to _____.
garik1379 [7]
The answer is b because the sun's surface temperature is 5,778 K.
5 0
3 years ago
Read 2 more answers
What is a natural resource used to make polypropylene?
Dmitry_Shevchenko [17]
<span>hydrocarbon (but im not 100% sure)</span>
4 0
3 years ago
Read 2 more answers
Believing that Nick will not be a good waiter because he is 60 years old is an example of O Stereotype O Prejudice Situational a
Helen [10]
Ya so quid fuh doil em yous
4 0
3 years ago
An Atwood machine is constructed using a hoop with spokes of negligible mass. The 2.3 kg mass of the pulley is concentrated on i
Sergeu [11.5K]

Answer:

a = 2.77~{\rm m/s^2}

Explanation:

Since the pulley has a mass concentrated on its rim, the pulley can be considered as a ring.

The moment of inertia of a ring is

I = mr^2 = (2.3)(23.5\times 10^{-2})^2 = 0.127

The mass on the left is heavier, that is the pulley is rotating counterclockwise.

By Newton's Second Law, the net torque is equal to moment of inertia times angular acceleration.

\tau = I \alpha

Here, the net torque is the sum of the weight on the left and the weight on the right.

\tau = m_1gR - m_2gR = (1.65)(9.8)(23.5\times 10^{-2}) - (1)(9.8)(23.5\times 10^{-2}) = 1.497~{\rm Nm}

Applying Newton's Second Law gives the angular acceleration

\tau = I\alpha\\1.497 = 0.127\alpha\\\alpha = 11.78~{\rm rad/s^2}

The relation between angular acceleration and linear acceleration is

a = \alpha R

Then, the linear acceleration of the masses is

a = 11.78 \times 23.5\times 10^{-2} = 2.77~{\rm m/s^2}

5 0
3 years ago
Other questions:
  • Is FeN compound ironic or covalent? how do you know?
    12·1 answer
  • A feather of mass 0.001 kg falls from a height of 2 m under realistic conditions it experiences air resistance based on what you
    9·2 answers
  • If you add a battery to a series circuit what will happen to the current in the circuit
    9·1 answer
  • An atomic nucleus is composed of A) protons. B) protons and neutrons. C) protons and electrons. D) protons, neutrons, and electr
    15·2 answers
  • What does the phrase rise over run refer to when defining slope
    5·1 answer
  • What is the wavelength of an earthquake wave if it has a speed of 13 km/s and a frequency of 5 Hz?
    15·1 answer
  • What is the voltage measured with a voltmeter across a wire in a circuit?
    6·2 answers
  • A wire of 1mm diameter and 1m long fixed at one end is stretched by 0.01mm when a lend of 10 kg is attached to its free end.calc
    5·1 answer
  • Which of the following are examples of etiquette? Check all of the boxes that apply.
    7·1 answer
  • 13. What is the ground state?
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!