What two functions does the evaporator of a domestic refrigerator perform?

A fisherman is fishing from a bridge and is using a "44.0-N test line." In other words, the line will sustain a maximum force of

vitfil [10]

Answer:

a) 4.485 kg b) 3.94 kg

Explanation:

since the maximum tension the line can stand is 44 N and for question a the speed is constant (acceleration must be zero since the velocity or speed is not changing), F(tension) = mass * acceleration due to gravity (g) .

44 = m * 9.81m/s^2

m = 44/9.81 = 4.485kg

b) F(tension) = ma + mg ( where a is the acceleration of the body and g is the acceleration of the gravity)

44 = m (a +g)

44 = m (1.37 + 9.81)

44/11.18 = m

m = 3.94 kg

3 0

3 years ago

A circle has an initial radius of 50ft when the radius begins decreasing at a rate of 2ft/s. what is the rate of change of the a

valkas [14]

The area of the circle with radius r is
A = πr²

The rate of change of area with respect to time is
$\frac{dA}{dt} = \frac{dA}{dr} . \frac{dr}{dt} =2 \pi r. \frac{dr}{dt}$

The rate of change of the radius is given as
$\frac{dr}{dt} =-2 \, \frac{ft}{s}$
Therefore
$\frac{dA}{dt} =-4 \pi r \, \frac{ft^{2}}{s}$

When r = 10 ft, obtain
$\frac{dA}{dt}|_{r=10 \, ft} = -40 \pi \, \frac{ft^{2}}{s}$

Answer: - 40π ft²/s (or - 127.5 ft²/s)

7 0

4 years ago

What type of energy can take up space

Arada [10]

Answer:

Yes energy does take up space.

Explanation:

Every form of energy has a defining characteristic; sound is the vibration of molecules, electricity is the movement of electrons, and mass is the thing that take up space.

8 0

3 years ago

A boy slides a book across the floor using a force of five and over a distance of 2M what is the kinetic energy of the book afte

Alinara [238K]

Answer: 10Nm or 10J

Explanation:

Given the following :

Force (f) = 5

Distance (d) = 2m

Calculate the kinetic energy assuming no friction

Work done = force × distance

Work done = 5N × 2m = 10Nm

Recall :

Work done = ΔK.E ( change in kinetic energy)

Therefore, kinetic energy of the book after sliding = ΔK. E, which is equal to work done.

Hence, K. E of book after sliding is 10Nm

5 0

3 years ago

what is the difference between kinetic energy and random motion of a cylider of oxygen carried by a car and one standing on a pl

pochemuha

Answer:

See explanation below

Explanation:

If we are talking about the kinetic energy of the cylinder of oxygen:

The kinetic energy possessed by any object is given by

$K=\frac{1}{2}mv^2$

where

m is the mass of the object

v is its speed

In this case, we have one cylinder carried by a car and one standing on a platform: this means that the speed of the cylinder carried by the car will be different from zero (and so also its kinetic energy will be different from zer), while the speed of the cylinder standing on the platform will be zero (and so its kinetic energy also zero). Therefore, the kinetic energy of the cylinder carried by the car will be larger than that standing on a platform.

Instead, if we are talking about the kinetic energy due to the random motion of the molecules of oxygen inside the cylinder:

The kinetic energy of the molecules in a gas is directly proportional to the absolute temperature of the gas:

$K=\frac{3}{2}kT$

where k is called Boltzmann constant and T is the absolute temperature of the gas. Therefore, we see that K does not depend on whether the gas is in motion or not, but only on its temperature - therefore, in this case there is no difference between the kinetic energy of the cylinder carried by the car and that standing on the platform (assuming they are at the same temperature)

6 0

3 years ago