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3 years ago

State the formula for calculating power

1 answer:

Alex3 years ago

7 0

Where power P is in watts, voltage V is in volts and current I is in amperes (DC).Power Formula 2 – Mechanical power equation: Power P = E ⁄ t where power P is in watts, Power P = work / time (W ⁄ t). Energy E is in joules, and time t is in seconds.

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For segment r and segment l to hold together, they must exert forces on each other. what is the direction of the force exerted o

Inga [223]

Thank you for posting your question here at brainly. I hope the answer will help you. Feel free to ask more questions.

The direction of the force exerted on segment r by segment l is left.

The forces on segment R are
1. the force due to L and
2. the pull (to the right) at the right end of the rope.

4 0

3 years ago

What happens to the density when water is poured into a empty glass?

san4es73 [151]

-- The density of the glass alone doesn't change.

-- The density of the water alone doesn't change.

-- The density of (the entire glass + everything IN IT) increases,
because the part that used to be air (with very low density) is
changed to water (with much higher density than the air had).

3 0

3 years ago

Water at 20 C flows through a 5-cm-diameter pipe that has a 180 vertical bend, as in Fig. P3.43. The total length of pipe betwee

Nataliya [291]

Answer:

F = 749 [N]

Explanation:

We must give full information on this problem, as well as the question that needs to be resolved.

Water at 20°C flows through a 5-cm-diameter pipe that has a 180° vertical bend. The total length of pipe between flanges 1 and 2 is 75 cm. When the weight flow rate is 230 N/s,

P1=165kPa

and

P2=134kPa

Neglecting pipe weight, determine the total force that the flanges must withstand for this flow.

We must make a U-shaped body diagram of the pipe in order to visualize the forces acting according to the pressures and the area of the pipe.

Then by means of the second law of motion of Newton, which says that the sum of the forces must be equal to the product of mass times acceleration, we can find the force Fp

Let us remember that pressure is defined as the divided force over the area, therefore:

F = P *A

where:

P = pressure

A = area

The product of the mass by acceleration, is equal to the product of the speed of the fluid by the mass flow, since we know the weight of the fluid we can find its mass flow.

$W_{flow}=230[N/s]\\W_{flow} =g*m_{flow}\\m_{flow} = W_{flow} / g\\m_{flow} = 230/9.81\\m_{flow}= 23.45[kg/s]$

In the function of the mass flow, we can find the velocity of the fluid, as we also know the diameter of the pipe

$m_{flow} = density*v*A\\where\\density = 1000[kg/m^{3}]\\ v= velocity[m/s]\\A = area [m^{2}]\\v=\frac{m_{flow}}{density*A} \\v=\frac{23.45}{1000*\frac{\pi}{4}*(5*10^{-2})^{2} } \\v= 11.94 [m/s]$

We know that the atmospheric pressure is equal to:

$P_{atm} = 101.325[kpa]$

The value of the pipe area is calculated for a circular section

$A = \frac{\pi}{4} * (0.05)^{2}\\ A = 0.00196[m^{2} ]$

The resultant force is 749 [N]

The solution of the equations and the free body diagram can be seen in the attached picture.

3 0

3 years ago

The block is sitting at rest on the floor. The normal force on

Ostrovityanka [42]

Answer:

Mass=0.305[kg]

Explanation:

The block is located on a surface, where no forces act on it, so it will remain at rest according to Newton's laws.

We can perform an analysis of forces on the y-axis (see the free body diagram) and in order to determine the equation to determine the mass of the body, we must remember that the value of a force influenced by gravity is equal to the product of mass by acceleration.

From this equation we can clear the value of the mass

6 0

3 years ago

What is the speed of light (in m/s) in air? (Enter your answer to at least four significant figures. Assume the speed of light i

jenyasd209 [6]

Answer:

The speed of light in air is 2.996x10⁸ m/s, and polystyrene is 1.873x10⁸ m/s.

Explanation:

To find the speed of light in air and in polystyrene we need to use the following equation:

$c_{m} = \frac{c}{n}$

Where:

$c_{m}$ : is the speed of light in the medium

n: is the refractive index of the medium

In air:

$c_{a} = \frac{c}{n_{a}} = \frac{2.997 \cdot 10^{8} m/s}{1.0003} = 2.996 \cdot 10^{8} m/s$

In polystyrene:

$c_{p} = \frac{c}{n_{p}} = \frac{2.997 \cdot 10^{8} m/s}{1.6} = 1.873 \cdot 10^{8} m/s$

Therefore, the speed of light in air is 2.996x10⁸ m/s, and polystyrene is 1.873x10⁸ m/s.

I hope it helps you!

8 0

3 years ago