All categories

2 years ago

Water is being heated in a closed pan on top of a range while being stirred by a paddle wheel.

1 answer:

6 0

Heat transfer in a closed system is the addition of changes in internal energy and the total amount of work done by it. The final energy of the system is 35.5kJ.

<h3>What is heat transfer? </h3>

Heat transfer is the transfer of heat energy due to temperature differences.

The paddle-wheel paintings are quantities of workdone, 500 N.m or 0.5kJ.

The preliminary (initial) power of the device is 10 kJ.

Total warmness transferred in the course of the method is 30 kJ

Total warmness misplaced in the course of the method to the encompassing air is 5 kJ.

The energy of the system is given as:

The energy of the system = Energy in - Energy out

The energy of the system = Initial energy + Energy transferred + Work done - Energy lost

Energy of the system = 10 + 30 + 0.5 - 5 kJ

Energy of the system = 35.5 kJ

You might be interested in

A compound has a melting point of 812°C. what type of bonding is in the compound?

AURORKA [14]

Answer:

Ionic compound.

Explanation:

812° C is a very high melting point. Such high melting points are generally ionic compound. Ionic compounds are have very strong bond between the elements ( electrostatic bond). In order to break this bond, large amount of heat energies are needed. So, they have high melting point. Also, Ionic compound are very good conductors of electricity.

7 0

3 years ago

A river flows due east at 12 km/h. A boat crosses the 720 m wide river by maintaining a constant velocity of 72 mi/h due north r

zhenek [66]

Answer:

The boat will be 74 .17 meters downstream by the time it reaches the shore.

Explanation:

Consider the vector diagrams for velocity and distance shown below.

converting 72 miles per hour to km/hr

we have 72 miles per hour 72 × 1.60934 = 115.83 km/hr

The velocity vectors form a right angled triangle, and can be solved using simple trigonometric laws

$tan \theta = \frac{12}{115.873}$

$\theta = tan^{-1}( \frac{12}{115.873})=5.9126$

This is the vector angle with which the ship drifts away with respect to its northward direction.

<em>From the sketch of the displacement vectors, we can use trigonometric ratios to determine the distance the boat moves downstream.</em>

Let x be the distance the boat moves downstream.d

$sin(5.9126)=\frac{x}{720}$

$x= 720\times 5.9126$

$x=74.17m$

∴The boat will be 74 .17 meters downstream by the time it reaches the shore.

6 0

4 years ago

A student heats a liquid on a burner. What happens to the portion of liquid that first begins to warm? Check all that apply.

kherson [118]

Answer:

The answers are options B,D and E

Explanation:

B) The particles in the liquid are slowly overcoming the forces of attraction and spreading out due to the thermal energy they are absorbing. This makes the liquid less dense as it slowly changes into a gas after reaching its boiling point.

D) The particles start absorbing the energy form the surroundings as latent heat of evaporation. They need this energy to overcome the strong forces of attraction between particles to change into the gaseous state

E) The particles have spaced out due to the thermal energy absorbed, making the liquid lighter and it rises upwards.

5 0

3 years ago

as an aid in understanding this problem. The drawing shows a positively charged particle entering a 0.61-T magnetic field. The p

miv72 [106K]

Answer:

E = 420.9 N/C

Explanation:

According to the given condition:

$Net\ Force = 2(Magnetic\ Force)\\Electric\ Force - Magnetic\ Force = 2(Magnetic\ Force)\\Electric\ Force = 3(Magnetic\ Force)\\qE = 3qvBSin\theta\\E = 3vBSin\theta$