Forces are never isolated because they come in... *

The block in the drawing has dimensions L0×2L0×3L0,where L0 =0.5 m. The block has a thermal conductivity of 200 J/(s·m·C˚). In d

Dennis_Churaev [7]

Answer:

$Q_p=18000\ J$

$Q_o=8000\ J$

$Q_g=72000\ J$

Explanation:

Given:

Length of block, $l=3L_o=3\times 0.5=1.5\ m$

Breadth of block, $b=L_o=0.5\ m$

height of block, $h=2L_o=2\times 0.5=1\ m$

Thermal conductivity of the block, $k=200\ W.m.^{\circ}C$

Temperature on the hotter side, $T_H=37^{\circ}C$

temperature on the cooler side, $T_L=7^{\circ}C$

time for which the heat flows, $t=4\ s$

REFER THE ATTACHED IMAGE FOR THE REFERENCE

The rate of heat flow using Fourier's law of conduction is given as:

$\frac{Q}{t}=k.A.\frac{dT}{dx}$

Now the amount heat flow perpendicular to the pink surface:

$\frac{Q_p}{4}=200\times (0.5\times 1.5).\frac{30}{1}$

$Q_p=18000\ J$

Now the amount heat flow perpendicular to the orange surface:

$\frac{Q_o}{4}=200\times (0.5\times 1).\frac{30}{1.5}$

$Q_o=8000\ J$

Now the amount heat flow perpendicular to the green surface:

$\frac{Q_g}{4}=200\times (1.5\times 1).\frac{30}{0.5}$

$Q_g=72000\ J$

6 0

3 years ago

An iron nail does not pick up paper clips as a magnet would. What can be concluded about the structure of the iron nail? It has

lesya692 [45]

Question: An iron nail does not pick up paper clips as a magnet would. What can be concluded about the structure of the iron nail?

Answer: It has domains that are not aligned.

Explanation: because the magnet is not allined its not gonna pick up anything metal cause its not alligned

question answered by

(jacemorris04)

4 0

4 years ago

Read 2 more answers

As an electron approaches a proton, the electron's force of attraction...

Tems11 [23]

Answer: B. Increases

Explanation:

An electron is a negatively charged particle, while a proton is positively charged.

Opposites attract so as it approaches the proton the force of attraction will increase.

7 0

3 years ago

What is it that makes a magnet different from a piece of iron that is not mangetic?

Alisiya [41]

Answer:

Under normal conditions, a magnetic material like iron doesn't behave like a magnet because the domains don't have a preferred direction of alignment. On the other hand, the domains of a magnet (or a magnetized iron) are all aligned in s specific direction.

7 0

3 years ago

A plastic film moves over two drums. During a 4-s interval the speed of the tape is increased uniformly from v0 = 2ft/s to v1 =

Ratling [72]

Answer:

Question 1)

a) The speed of the drums is increased from 2 ft/s to 4 ft/s in 4 s. From the below kinematic equations the acceleration of the drums can be determined.

$v_1 = v_0 + at \\4 = 2 + 4a\\a = 0.5~ft/s^2$

This is the linear acceleration of the drums. Since the tape does not slip on the drums, by the rule of rolling without slipping,

$v = \omega R\\a = \alpha R$

where α is the angular acceleration.

In order to continue this question, the radius of the drums should be given.

Let us denote the radius of the drums as R, the angular acceleration of drum B is

α = 0.5/R.

b) The distance travelled by the drums can be found by the following kinematics formula:

$v_1^2 = v_0^2 + 2ax\\4^2 = 2^2 + 2(0.5)x\\x = 12 ft$

One revolution is equal to the circumference of the drum. So, total number of revolutions is

$x / (2\pi R) = 6/(\pi R)$

Question 2)

a) In a rocket propulsion question, the acceleration of the rocket can be found by the following formula:

$a = \frac{dv}{dt} = -\frac{v_{fuel}}{m}\frac{dm}{dt} = -\frac{13000}{2600}25 = 125~ft/s^2$

b) $a = -\frac{v_{fuel}}{m}\frac{dm}{dt} = - \frac{13000}{400}25 = 812.5~ft/s^2$

5 0

4 years ago