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
Mrac [35]
3 years ago
11

A tree loses water to the air by the process of transpiration at the rate of 110 g/h. This water is replaced by the upward flow

of sap through vessels in the trunk. If the trunk contains 2000 vessels, each 100 mm in diameter, what is the upward speed of the sap in each vessel? The density of tree sap is 1040 kg/m3.
The answer is 187 nm/s. Although, I don't know how they got that answer because my numbers and units are different.
Physics
1 answer:
Ksivusya [100]3 years ago
8 0

Answer:

The answer is 1.87nm/s.

Explanation:

The 110g/hr  water loss must be replaced by 110g/hr of sap. 110g of sap corresponds to a volume of  

110g \div \dfrac{1040*10^3g}{1*10^6cm^3}  = 106cm^3

thus rate of sap replacement is

106cm^3/hr = 106*10^{-6}m^3/3600s  = 2.94*10^{-8}m^3/s

The volume of sap in the vessel of length x is

V = Ax,

where A is the cross sectional area of the vessel.

For 2000 such vessels, the volume is

V = 2000Ax

taking the derivative of both sides we get:

\dfrac{dV}{dt} = 2000A \dfrac{dx}{dt}

on the left-hand-side \dfrac{dx}{dt} is the velocity v of the sap, and on right-hand-side \dfrac{dV}{dt}  = 2.94*10^{-8}m^3/s; therefore,

2.94*10^{-8}m^3/s=2000Av

and since the cross-sectional area is

A = \pi (\dfrac{100*10^{-3}m}{2} )^2 = 7.85*10^{-3}m^2;

therefore,

2.94*10^{-8}m^3/s =2000(7.85*10^{-3}m^2)v

solving for v we get:

v = \dfrac{2.94*10^{-8}m^3/s}{2000(7.85*10^{-3}m^2)}

\boxed{v =1.875*10^{-9}m/s = 1.875nm/s}

which is the upward speed of the sap in each vessel.

You might be interested in
A book rests on a wooden table is an example of
kykrilka [37]

Answer:

Static friction

Explanation:

When there is contact between two surfaces and there is no movement, there is static friction. So, if we have a book that rests on a wooden table, we have an example of Static friction, where this force avoids the movement of the book.

7 0
1 year ago
A person pushes a refrigerator across a horizontal floor. The mass of the refrigerator is 110 kg, the coefficient of static fric
Law Incorporation [45]

Answer:

Explanation:

mass of refrigerator, m = 110 kg

coefficient of static friction, μs = 0.85

coefficient of kinetic friction, μk = 0.59

(a) the minimum force required to just start the motion in refrigerator

F = μs x mg

F = 0.85 x 110 x 9.8

F = 916.3 N

(b) The force required to move the refrigerator with constant speed

F' = μk x mg

F' = 0.59 x 110 x 9.8

F' = 636.02 N

(c) Let a be the acceleration.

Net force = Applied force - friction force

F net = 950 - 636.02

F net = 313.98 N

a = F net / mass

a = 313.98 / 110

a = 2.85 m/s²

4 0
3 years ago
A mountain-climber friend with a mass of 74 kg ponders the idea of attaching a helium-filled balloon to himself to effectively r
bazaltina [42]

Answer:

V=16.65 m^3

Explanation:

The volume of the balloon can be find compared the force in each cases so:

reduce 25% from 74kg

R=\frac{25}{100}*74kg=18.5kg

So the net force uproad on the balloon is

F_b=18.5kg*g

Now the density of the both gases air and helium are different however the volume is the same change offcorss the mass so:

P_h=\frac{m}{V}=0.179 kg/m^3

P_A=1.29 kg/m^3

F_b=F_A-F_H

F_b=m_a*g-m_h*g

m=P/V

18.5kg*g=(1.29kg/m^3-0.179kg/m^3*)V*g

V=\frac{18.5kg}{(1.29-0.179)kg/m^3}

V=16.65 m^3

4 0
3 years ago
A Van de Graaff generator is one of the original particle accelerators and can be used to accelerate charged particles like prot
Rzqust [24]

Answer:

595391.482946 m/s

3.21875\times 10^{6}

Explanation:

E = Energy = 1.85 keV

I = Current = 5.15 mA

e = Charge of electron = 1.6\times 10^{-19}\ C

t = Time taken = 1 second

m = Mass of proton = 1.67\times 10^{-27}\ kg

Velocity of proton is given by

v=\sqrt{\dfrac{2E}{m}}\\\Rightarrow v=\sqrt{\dfrac{2\times 1.85\times 10^3\times 1.6\times 10^{-19}}{1.67\times 10^{-27}}}\\\Rightarrow v=595391.482946\ m/s

The speed of the proton is 595391.482946 m/s

Current is given by

I=\dfrac{\Delta Q}{t}\\\Rightarrow \Delta Q=It\\\Rightarrow \Delta Q=5.15\times 10^{-3}\times (1\ sec)\\\Rightarrow Q=5.15\times 10^{-3}\ C

Number of protons is

n=\dfrac{Q}{e}\\\Rightarrow n=\dfrac{5.15\times 10^{-3}}{1.6\times 10^{-19}}\\\Rightarrow n=3.21875\times 10^{6}\ protons

The number of protons is 3.21875\times 10^{6}

3 0
3 years ago
Sodium and phosphorus combine to form Na3P. The name of this compound is .
g100num [7]
Binary ionic compound
5 0
2 years ago
Read 2 more answers
Other questions:
  • Would the weight density of water be different on the moon than it is on earth?
    5·1 answer
  • Which of the following characteristics is not a quality of digital media
    7·1 answer
  • The best base unit for measuring the length of a carpet is a ____
    8·2 answers
  • What is responsible for initiating a signal transduction pathway?
    14·1 answer
  • A bicycle traveled 150 meters west from point A to point B. Then it took the same route and came back to point A. It took a tota
    8·1 answer
  • A 200-Ω resistor is connected in series with a 10-µF capacitor and a 60-Hz, 120-V (rms) line voltage. If electrical energy costs
    15·1 answer
  • Two equal charges of magnitude 1.1 x 10 -7 C experience an electrostatic force of 4.2 x 10-4 N. How far apart are the centers of
    5·1 answer
  • Pls help me quick im doing a quiz
    9·2 answers
  • Forces at a Distance
    14·1 answer
  • Assume that a vaulter is able to carry a vaulting pole while running as fast as Carl Lewis in his world record 100-m dash (aroun
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!