The effort is always less than the load for a second-class lever. <br><br> true or false

Water enters an ice machine at 55F and leaves as ice at 25F. If the COP of the ice machine is 3.7 during this operation, determi

boyakko [2]

Answer:

The required power is $P_i = 0.2692 \ hp$

Explanation:

From the question we are told that

The temperature of the water entering ice machine is $T_1 = 55 ^o F$

The temperature of the water leaving is $T_2 = 25 ^oF$

The COP of the ice machine is $COP= 3.7$

The production rate of an ice $\r m = 15.0 \ lbm /hr$

The energy that needs to removed from each lbm of water at 55 F is $E = 169 Btu$

Generally the cooling load of the ice machine is mathematically represented as

$\r Q_L = \r m * E$

$\r Q_L =15 * 169$

=> $\r Q_L = 2535 \ Btu/h$

Generally the COP of the ice machine is mathematically represented as

$COP = \frac{\r Q_L}{P_i}$

Here $P_i$ is the net power input needed to successfully run the ice machine

So

$3.7 = \frac{2535}{P_i}$

=> $P_i = 685 \ Btu/h$

Converting to horsepower

$P_i = \frac{685}{2545}$

=> $P_i = 0.2692 \ hp$

3 0

3 years ago

Moving a magnet quickly in and out of a coil of wire produces _____.

Oksanka [162]

<span>An electric current.</span>

8 0

4 years ago

Work out the kinetic energy of a 2.5 kg remote-controlled car that is moving at 2 m/s.

lbvjy [14]

Answer: 5 joules

Explanation:

mass=m=2.5kg

Velocity=v=2m/s

Kinetic energy=ke

ke=(m x v x v)/2

ke=(2.5 x 2 x 2)/2

Ke=10/2

Ke=5

Kinetic energy=5 joules

8 0

3 years ago

Which type of reaction does this diagram represent?

Ugo [173]

The diagram represents a chain reaction that is caused by nuclear fission.

<h3>What is a nuclear fission reaction?</h3>

A nuclear fission reaction is a reaction in which the nucleus of a larger atom is split into two or more smaller nucleus of atoms.

Nuclear fission can proceed in the form of a chain reaction in which the products of the first fission reaction are used to initiate further fission reactions.

Therefore, the diagram represents a chain reaction that is caused by nuclear fission.

Learn more about nuclear fission at: brainly.com/question/22155336

#SPJ1

4 0

2 years ago

Read 2 more answers

A block of ice(m = 14.0 kg) with an attached rope is at rest on a frictionless surface. You pull the block with a horizontal for

nadezda [96]

Answer:

a) The weight and the normal force of the block has a magnitude of 137.298 newtons and the pull force exerted on the block has a magnitude of 98 newtons.

b) The final speed of the block of ice is 9.8 meters per second.

Explanation:

a) We need to calculate the weight, normal force from the ground to the block and the pull force. By 3rd Newton's Law we know that normal force is the reaction of the weight of the block of ice on a horizontal.

The weight of the block ( $W$ ), measured in newtons, is:

$W = m\cdot g$ (1)

Where:

$m$ - Mass of the block of ice, measured in kilograms.

$g$ - Gravitational acceleration, measured in meters per square second.

If we know that $m = 14\,kg$ and $g = 9.807\,\frac{m}{s^{2}}$ , the magnitudes of the weight and normal force of the block of ice are, respectively:

$N = W = (14\,kg)\cdot \left(9.807\,\frac{m}{s^{2}} \right)$

$N = W = 137.298\,N$

And the pull force is:

$F_{pull} = 98\,N$

The weight and the normal force of the block has a magnitude of 137.298 newtons and the pull force exerted on the block has a magnitude of 98 newtons.

b) Since the block of ice is on a frictionless surface and pull force is parallel to the direction of motion and uniform in time, we can apply the Impact Theorem, which states that:

$m\cdot v_{o} +\Sigma F \cdot \Delta t = m\cdot v_{f}$ (2)