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3 years ago

Which of the following is not a type of pulley system

2 answers:

8 0

D advantageousA pulley is a wheel on an axle or shaft that is designed to support movement and change of ... The drive element of a pulley system<span> can be a rope, cable, belt, or chain that runs over the pulley.</span>

NikAS [45]3 years ago

3 0

I think the answer is D: advantageous

You might be interested in

When waves of equal amplitude from two sources are in phase when they interact, it is called ________.?

8090 [49]

The answer is constructive interference. At the point when two waves meet such that their peaks line up together, then it's called productive obstruction. The subsequent wave has a higher adequacy. In dangerous obstruction, the peak of one wave meets the trough of another, and the outcome is a lower add up to adequacy.

3 0

3 years ago

Cause and Effect: What would happen to a space vehicle in orbit around Earth if it sped up?

gulaghasi [49]

Answer:

G M m / R^2 = m v^2 / R gravitational force = centripetal force

G M = v^2 R = constant

As v increases R will must decrease

Take the moon as an example

S = 2 pi R where R is about 240,000 miles for one orbit

S / 1 day = 54,000 miles/day for a 28 day circuit

S / 1 hr = 54000 / 24 = 2200 mph which is much less than a satellite in orbit

4 0

3 years ago

A single insulated duct flow experiment using air operating at steady-state is performed in a lab. One measurement location (Sta

weqwewe [10]

Answer:

a) -0.0934 kJ/kg. K

b) The direction of flow is from right to left.

Explanation:

A free flow diagram of the horizontal insulated duct is as shown below.

NOW,

Let assume that the direction of flow is from left to right and consider the following relation for the entropy rate balance equation for a control volume as:

$\frac{\sigma_{cv}}{m}= (s_2-s_1) \geq 0 \ \ \ -------> \ \ \ 1$

Now; if the value for this relation is greater than zero; then we conclude that our assumption is correct.

If the value is less than zero; then we conclude that the assumption is wrong.

Then, the flow is said to be in the opposite direction

Formula for the change in specific entropy can be calculated as:

$s_2-s_1 = s^0(T_2) - s^0(T_1)-R \ In ( \frac{P_2}{P-1}) \ \ \ -------> \ \ \ 2$

where;

$s_1, s_2 , s^0(T_2), s^0(T1)$ are specific entropies

R = universal gas constant

$P_1$ = pressure at location 1

$P_2$ = pressure at location 2

We obtain the specific properties of air at temperature at $T_1$ = (67°C + 273)K = 340 K from the table A-22 ( Ideal gas properties of air)

$s^0(T1)$ = 1.8279 kJ/kg.K

We also obtain the specific properties of air at temperature $T_2$ = 22°C + 273) K = 295 K

From the table A- 22

$s^0(T_2)$ = 1.68515 kJ/kg . K

R = $\frac{8.314 kJ}{28.97 kg.K}$

$P_1 =$ 0.95 bar

$P_2 =$ 0.8 bar

Now replacing our values into equation (2) from above; we have;

$s_2-s_1 = s^0(T_2) -s^0(T_1)-R \ In (\frac{P_2}{P_1} )$

$s_2-s_1 = 1.68515 -1.8279-\frac{8.314}{28.97} \ In (\frac{0.8}{0.95} )$

$s_2-s_1 = 1.68515 -1.8279+ 0.0493$

$s_2-s_1 =-0.0934 \ kJ/kg.K$

Equating our result to equation (1)

$s_2-s_1 \geq 0\\-0.0934 \leq 0$

Therefore , our assumption is wrong and the direction of flow is said to be from right to left.

We therefore conclude that the direction of flow is from right to left.

3 0

4 years ago

Una barra de aluminio que esta a 78 GRADOS CENTIGRADOS entra en contacto con una barra de cobre de la misma longitud y área que

stiks02 [169]

Answer:

Al llegar a su equilibrio térmico ambas barran tendrán una temperatura de 53 grados centígrados.

Explanation:

Dado que una barra de aluminio que está a 78 grados centígrados entra en contacto con una barra de cobre de la misma longitud y área que esta a 28 grados centígrados, y posteriormente se lleva acabo la transferencia de energía entre ambas barras llegando a su equilibrio térmico, para determinar la temperatura a la que ambas barras llegarán se debe realizar el siguiente cálculo:

(78 + 28) / 2 = X

106 / 2 = X

53 = X

Por lo tanto, al llegar a su equilibrio térmico ambas barran tendrán una temperatura de 53 grados centígrados.

8 0

3 years ago

A physics instructor wants to project a spectrum of visible-light colors from 400 nm to 700 nm as part of a classroom demonstrat

Likurg_2 [28]

Answer:

Dr = 263 10⁻⁶ m

Explanation:

The diffraction pattern for constructive interference is described by

a sin θ = m λ

in this it indicates that the order of diffraction is m = 1

Let's use a direct proportion rule to find the separation of two slits. If there are 600 lines in 1 me, what is the distance between 2 slits

a = 2 lines 1/600

a = 2/600

a = 3.33 10⁻³ mm = 3.33 10⁻⁴ cm

let's use trigonometry

tan θ = y / L

as the measured angles are small

tan θ = sin θ / cos θ sin θ

sin θ = y / L

we substitute

a y/L = λ

y = λ L / a

for λ = 400 10-9 m

I = 400 10⁻⁹ 2.9 / 3.33 10⁻³

i = 346.89 10⁻⁶ m

or λ = 700 nm

y_f = 700 10⁻⁻⁹ 2.9 / 3.33 10⁻³

y_f = 609.609 10⁻⁶ m

the separation of this spectrum

Δr = v_f - i

Dr = (609.609 - 346) 10 ⁻⁶

Dr = 263 10⁻⁶ m

4 0

3 years ago