If an upstairs room is warmer than downstairs, is that a example of convection, conduction, or radiation?

You have a reservoir held at a constant temperature of –30°C. You add 400 J of heat to the reservoir. If you have another reserv

marysya [2.9K]

Answer:

449.38 J

Explanation:

ΔS = ΔQ/T

Where ΔS = entropy change

Q = quantity of heat

T = temperature

First reservoir :

T = –30°C = - 30 + 273 = 243K

Q = 400 J

Second reservoir :

T = 0°C = 273K

Q =?

To have same increase in entropy for both reservoirs :

Q/T of first reservoir = Q/T of second reservoir

400/243 = Q/273

243 * Q = 400 * 273

Q = (400 * 273) / 243

Q = 109,200 / 243

Q = 449.38271

Q = 449.38 J

6 0

3 years ago

True or false? Scientific theories lack experimental support

goldenfox [79]

Answer:

Hey there!

It is false. Theories can be repeatedly tested to give people an explanation of the world.

Let me know if this helps :)

8 0

3 years ago

What biomes are found in southern africa?

Sindrei [870]

The biomes found in Southern Africa contains: Grassland, Thicket, Savanna, Succulent Karoo, Nama Karoo, Forest, Fynbos, and Desert

7 0

3 years ago

Identify each unit as belonging to SI units or US Customary units.

torisob [31]

Answer:

<em>SI Units</em>

Meter

Kilogram

Kelvin

<em>US Customary Units and English Units</em>

Gallon

Mile

Pound

Degrees Fahrenheit

Explanation:

The SI units or International System of Units are the widely used metrics of measuring a physical quantity. It has specific abbreviations.

The US customary units is a measurement system where it is widely used in the united states. This system of unit also has abbreviations.

There are also conversion scales that are used to convert a unit from one metric system to the other.

For example, the conversion of mile to SI unit is given by the formula

1 mile = 1609.4 meters

Similarly,

1 pound = 0.453592 Kg

6 0

3 years ago

SOMEBODY PLEEASEEE HELP A STRUGGLING HIGHSCHOOLERRRR +(

CaHeK987 [17]

Explanation:

What is the weight of a 2.00-kilogram object on the surface of Earth?

2.00 N

4.91 N

9.81 N

19.6 N

Given parameters:

Mass of the object = 2kg

Unknown:

Weight of the object = ?

Solution:

The weight of an object is the force of gravity acting on the object;

Weight = mass x acceleration due to gravity

Acceleration due to gravity = 9.8m/s²

Now insert the parameters and solve;

Weight = 2 x 9.8 = 19.6N

A person weighing 785 Newtons on the surface of the Earth would weigh 47 Newtons on the surface of Pluto. What is the magnitude of the gravitational acceleration on the surface of Pluto?

1.7 m/s²

0.59 m/s²

0.29 m/s²

9.8 m/s²

Given parameters:

Weight on Earth = 785N

Weight on Pluto = 47N

Unknown:

Acceleration due to gravity on Pluto = ?

Solution

The mass of the body both on Earth and Pluto is the same.

Weight = mass x acceleration due to gravity

Now find the mass on Earth;

Acceleration due to gravity on Earth = 9.8m/s²

785 = mass x 9.8

mass = $\frac{785}{9.8}$ = 80.1kg

So;

Acceleration due to gravity on Pluto = $\frac{Weight on Pluto}{mass }$

Acceleration due to gravity = $\frac{47}{80.1}$ = 0.59m/s²

5 0

2 years ago