answer.
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
Andrews [41]
2 years ago
7

A thin electrical heating element provides a uniform heat flux qo" to the outer surface of a duct through which air flows. The d

uct wall has a thickness of 10 mm and a thermal conductivity of 20 W/m·K. (a) At a particular location, the air temperature is 30°C and the convection heat transfer coefficient between the air and inner surface of the duct is 100 W/m2·K. What heat flux is required to maintain the inner surface of the duct at Ti = 58°C? (b) For the conditions of part (a), what is the temperature To of the duct surface next to the heater?
Physics
1 answer:
Ivanshal [37]2 years ago
5 0

Answer:

a)q= 2800 W/m²

b)To=59.4°C

Explanation:

Given that

L = 10 mm

K= 20 W/m·K

T=30°C

h= 100 W/m²K

Ti=58°C

a)

Heat flux q

q= h ΔT

q= 100 x (58 - 30 )

q= 2800 W/m²

b)

As we know that heat transfer by Fourier law given as

Q= K A ΔT/L

Lets take outer temperature is To

So by  Fourier law

To= Ti + qL/K

Now by putting the values

To= Ti + qL/K

To= 58 + 2800 \times \dfrac{ 0.01}{20}

To=59.4°C

You might be interested in
A 3.00-kg ball swings rapidly in a complete vertical circle of radius 2.00 m by a light string that is fixed at one end. The bal
Setler [38]

Answer

given,

mass of the ball = 3 kg

swing in vertical circle with radius = 2 m

   work done by the gravity = ?          

   work done by the tension = ?            

Work done by the gravity = - m g Δh            

 Δ h = 2 + 2 = 4 m                                                                

Work done by the gravity =- 3 \times 9.8 \times 4

                                           = -117.6 J                  

work done by gravity is equal to -117.6 J            

Work done by tension will be equal to zero.        

Zero because tension is always perpendicular to velocity

work done by tension is equal to 0 J                          

7 0
2 years ago
Among the largest passenger ships currently in use, the Norway has been in service the longest. The Norway is more than 300 m lo
LenaWriter [7]

Answer:

6.33\times 10^8\ kg\cdot m/s

Explanation:

Mass of the ship (m) = 6.9 × 10⁷ kg

Speed of the ship (v) = 33 km/h

First, let us convert the speed from km/h to m/s using the conversion factor.

We know that, 1 km/h = 5/18 m/s

So, 33 km/h = 33\times \frac{5}{18}=9.17\ m/s

Now, we know, the momentum of an object only depends on its mass and speed. Momentum is independent of the length of the object.

So, here, length of the ship doesn't play any role in the determination of the momentum.

Magnitude of momentum of the ship = Mass × Speed

                                                             = (6.9\times 10^7\ kg)(9.17\ m/s)

                                                             = 6.33\times 10^8\ kg\cdot m/s

Therefore, the magnitude of ship's momentum is 6.33\times 10^8\ kg\cdot m/s.

6 0
2 years ago
Two vectors A and B are directed such that there is an angle θ between them. show answer Incorrect Answer Which of the following
Troyanec [42]

Answer:

Scalar product is between ║A║ ║ B║ and  -║A║ ║ B║

Explanation:

Dot product between vec A and vec B is

A.B  = ║A║ ║ B║  cos θ

Here, both ║A║ and ║B║ are positive and value of cos θ depends upon θ  and lies between 1 and -1

So, Scalar product is between ║A║ ║ B║ and  -║A║ ║ B║

8 0
2 years ago
Robin Hood wishes to split an arrow already in the bull's-eye of a target 40 m away.
tamaranim1 [39]

Answer:

5.843 m

Explanation:

suppose that the arrow leave the bow with a horizontal speed , towards he bull's eye.

lets consider that horizontal motion

distance = speed * time

time = 40/ 37 = 1.081 s

arrow doesnot have a initial vertical velocity component. but it has a vertical motion due to gravity , which may cause a miss of the target.

applying motion equation

(assume g = 10 m/s²)

s=ut+\frac{1}{2}*gt^{2}  \\= 0+\frac{1}{2}*10*1.081^{2}\\= 5.843 m

Arrow misses the target by 5.843m ig the arrow us split horizontally

4 0
2 years ago
The expressions for e/m and the relative error of e/m due to all of the parameters measured:
bija089 [108]

Answer:

Term 1 = (0.616 × 10⁻⁵)

Term 2 = (7.24 × 10⁻⁵)

Term 3 = (174 × 10⁻⁵)

Term 4 = (317 × 10⁻⁵)

(σ ₑ/ₘ) / (e/m) = (499 × 10⁻⁵) to the appropriate significant figures.

Explanation:

(σ ₑ/ₘ) / (e/m) = (σᵥ /V)² + (2 σᵢ/ɪ)² + (2 σʀ /R)² + (2 σᵣ /r)²

mean measurements

Voltage, V = (403 ± 1) V,

σᵥ = 1 V, V = 403 V

Current, I = (2.35 ± 0.01) A

σᵢ = 0.01 A, I = 2.35 A

Coils radius, R = (14.4 ± 0.3) cm

σʀ = 0.3 cm, R = 14.4 cm

Curvature of the electron trajectory, r = (7.1 ± 0.2) cm.

σᵣ = 0.2 cm, r = 7.1 cm

Term 1 = (σᵥ /V)² = (1/403)² = 0.0000061573 = (0.616 × 10⁻⁵)

Term 2 = (2 σᵢ/ɪ)² = (2×0.01/2.35)² = 0.000072431 = (7.24 × 10⁻⁵)

Term 3 = (2 σʀ /R)² = (2×0.3/14.4)² = 0.0017361111 = (174 × 10⁻⁵)

Term 4 = (2 σᵣ /r)² = (2×0.2/7.1)² = 0.0031739734 = (317 × 10⁻⁵)

The relative value of the e/m ratio is a sum of all the calculated terms.

(σ ₑ/ₘ) / (e/m)

= (0.616 + 7.24 + 174 + 317) × 10⁻⁵

= (498.856 × 10⁻⁵)

= (499 × 10⁻⁵) to the appropriate significant figures.

Hope this Helps!!!

6 0
2 years ago
Other questions:
  • A projectile follows a straight-line path instead of a parabolic trajectory. Which could be the launch angle? would it be 90 or
    9·2 answers
  • A 25.0-kg child plays on a swing having support ropes that are 2.20 m long. Her brother pulls her back until the ropes are 42.0°
    5·1 answer
  • Select True or False for the following statements about Heisenberg's Uncertainty Principle. True False It is not possible to mea
    5·1 answer
  • A truck of mass mT = 2000 kg is going north on Guadalupe with a speed of 4 m/s. The truck is struck by an eastbound car (mass of
    14·1 answer
  • a rectangular coil of 25 loops is suspended in a field of 0.20wb/m2.the plane of coil is parallel to the direction of the field
    7·1 answer
  • Thermodynamic Properties: Two identical, sealed, and well-insulated jars contain different gases at the same temperature. Each c
    12·1 answer
  • Devise and draw a circuit using a long, straight wire resistor, instead of a decade box, that would allow the study of the varia
    10·1 answer
  • An ideal monatomic gas initially has a temperature of T and a pressure of p. It is to expand from volume V1 to volume V2. If the
    10·1 answer
  • In seismology, the P wave is a longitudinal wave. As a P wave travels through the Earth, the relative motion between the P wave
    13·1 answer
  • Ever tried to stop a 150-pound (68 kg) cannonball fired towards you at 30 mph (48 km/hr.)? No, probably not. But you may have tr
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!