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
Nitella [24]
3 years ago
6

A solid-propellant rocket has chamber pressure of 6.35 atm with propellant density of 3.8 g/cm3 and burn area of 975 cm2 . Find

the total burn time (in seconds) if the propellant mass is 320 kg.
Physics
1 answer:
cupoosta [38]3 years ago
4 0

Answer:

Explanation:

Given:

P = 6.35 atm

= 1.01 × 10^5 × 6.35

= 6.434 × 10^5 N/m^2

As = 975 cm^2

D = 3.8 g/cm^2

M = 320 kg

Since the propellant volume is equal to the cross sectional area, As times the fuel length, the volumetric propellant consumption rate is the cross section area times the linear burn rate, bs , and the instantaneous mass flow rate of combustion, ms gases generated is equal to the volumetric rate times the fuel density, D

ms = D × As × bs

ms ÷ bs = M/L

M/L = 3.8 × 975

= 3705 g/cm

= 3.705 × 10^6 kg/m^3

Pressure = mass × g/area

= mass/length × time^2

t = sqrt(3.705 × 10^6/6.43 × 10^5)

= 2.4 s

You might be interested in
A 15.0 mW laser puts out a narrow beam 2.00 mm indiameter.
Murljashka [212]

Answer:

1341.03 V/m

Explanation:

The power output per unit area is the intensity and also the is the magnitude of the Poynting vector.

                                 S = \frac{P}{A} = cε₀E^{2} _{rms}

                             ⇒ \frac{P}{A} = cε₀E^{2}_{rms}

Where;

P is the power output

A is the area of the beam

c is speed of light

ε₀ is permittivity of free space 8.85 × 10⁻¹² F/m

E_{rms} is the average (rms) value of electric field

Making electricfield E_{rms} the subject of the equation

                                 E^{2}_{rms} = P / Acε₀

                                 E_{rms} = √(P / Acε₀)

But area A = πr²

                                 E_{rms} = √(P / πr²cε₀)                    

Given:

Output power, P = 15 mW = 0. 015 W

Diameter, d = 2 mm = 0.002 m

⇒ Radius, r = \frac{d}{2} = \frac{0.002}{2} = 0.001 m

Solving for average (rms) value of electric field;     

E_{rms} = \sqrt{\frac{0.015 W}{\pi * (0.001 m)^2 * (3 * 10^8 m/s) * (8.85 * 10^-12) C^2/Nm^2} }

                                E_{rms} = 1341.03 V/m

                             

                         

                                 

                                 

                                 

6 0
3 years ago
A ball is falling from the second floor balcony to the floor below
aleksandrvk [35]

Answer:

KE increases and PE decreases

Explanation:

7 0
2 years ago
Read 2 more answers
What is an isotope ?
Step2247 [10]

<span>An isotope is a form of a chemical element whose atomic nucleus contains a specific number of neutrons in addition to the number of protons that distinctively defines the element. The nuclei of most atoms have neutrons as well as protons.</span>

8 0
3 years ago
What is the numerical value of the slope of the line (without units)?<br>0.083<br>24<br>8.3<br>12
tankabanditka [31]
As close as I can read it, it appears to be

                 1/12  gram/second

           (0.08333... gm/sec)
4 0
3 years ago
About how long have wastewater treatment plants been in existence? about how long have wastewater treatment plants been in exist
ella [17]
Water treatment plants have been in existence for almost 220 years
8 0
3 years ago
Other questions:
  • a field hockey ball is launched from the ground at an angle to the horizontal. what are the ball's horizontal and vertical accel
    11·1 answer
  • Suppose the lift force on the plane in the diagram below was larger than the force of gravity. Which of the following statements
    5·1 answer
  • Two long straight wires carry currents perpendicular to the xy plane. One carries a current of 50 A and passes through the point
    11·1 answer
  • A rifle bullet with a mass of 11.5 g traveling toward the right at 251 m/s strikes a large bag of sand and penetrates it to a de
    14·1 answer
  • Compare the properties of sodium chloride and sand
    6·1 answer
  • 3) The energy resulting from motion is called
    5·1 answer
  • Memories
    11·1 answer
  • A person is lifted 24 meters by the elevator in a building. If the
    9·1 answer
  • A football player kicks a football, from ground level, with an initial velocity of 27.0 m/s at an angle 30° above the horizontal
    11·1 answer
  • HELP PLS HELP. WILL GIVE BRAINLIEST.
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!