Ask question

Ask question

All categories

Dmitry_Shevchenko [17]

4 years ago

8

Joan stirred a pot of hot soup with a metal spoon. after a minute or two, the handle of the spoon became too hot to hold. what k

ind of heat transfer does this represent?

1 answer:

natima [27]4 years ago

4 0

When the metal spoon comes in contact with the hot soup, heat transfer from hot soup to the spoon because of difference in temperature of the two. The kind of heat transfer represented here is conduction. In conduction, heat is transferred from a region of higher temperature to a region of lower temperature when there is a physical contact between the two.

You might be interested in

Hii:) anyone able to explain and help me with this question?

Assoli18 [71]

Answer:

No

Explanation:

The equation of state for ideal gases tells that:

$pV=nRT$

where

p is the gas pressure

V is the gas volume

n is the number of moles of the gas

R is the gas constant

T is the absolute temperature

In this problem, we have a fixed mass of gas. This means that the number of moles of the gas, $n$ , does not change; also, the volume V remains the same, and R is a constant, this means that

$p\propto T$

So, as the pressure increases, the temperature increases.

However, here we want to understand what happens to the average distance between the molecules.

We have said previously that the number of moles n does not change: and therefore, the total number of molecules in has does not change either.

If we consider one dimension only, we can say that the average distance between the molecules is

$d=\frac{L}{N}$

where L is the length of the container and N the number of molecules. Since the volume of the container here does not change, L does not change, and since N is constant, this means that the average distance between the molecules remains the same.

4 0

3 years ago

How to find the value of sin(90+ theta) ?

koban [17]

Sin(90 + θ)

By addition angle formula for sine.

sin90cosθ + cos90sinθ

1*cosθ + 0*sinθ

cosθ + 0

= cosθ

sin(90 + θ) = cosθ

6 0

3 years ago

HELP!! Explain why a more streamlined car generally will have a better fuel economy than a bulkier car with the same mass.

Nat2105 [25]

Streamlined means less air resistance. The car will need less force so less fuel in order to overcome air resistance. This will make it more fuel efficient.

6 0

3 years ago

Read 2 more answers

Okay please help me all my assignments are due tomorrow! I need to know 5 examples of all 6 simple machines that can be found in

iren [92.7K]

Answer:

Inclined Plane – A ramp, for example a wheelchair ramp. Paired inclined planes make a pitched roof.

Wheel & Axle – On lawnmowers and wheelbarrow. Also, found in cabinet door glides and on appliances. Another common example – door knobs and even inside those locksets.

Lever – The bottle opener. Tools – the crowbar, and scissors or pliers. Double Levers – a door, a toilet seat, a broom.

Pulley – Old wood windows, some garage doors, workshop or garage lifting systems.

Wedge – The shim – used throughout the home in construction. For example, when installing doors, windows, cabinets, etc. Sometimes used to level furniture or chairs.

Screw – Like the wedge, above, well, you couldn’t build a house without screws. Certain types of plumbing valves. Plus, a jar lid is a popular example.

Now for deeper look at the simple machines found around our homes.

The hope this will be helpful.

3 0

3 years ago

Two floors in a building are separated by 4.1 m. People move between the two floors on a set of stairs. (a) Determine the change

Ket [755]

Answer:

a) The change in potential energy of a 3.0 kilograms backpack carried up the stairs.

b) The change in potential energy of a persona with weight 650 newtons that descends the stairs is -2665 joules.

Explanation:

Let consider the bottom of the first floor in a building as the zero reference ( $z = 0\,m$ ). The change in potential energy experimented by a particle ( $\Delta U_{g}$ ), measured in joules, is:

$\Delta U_{g} = m\cdot g\cdot (z_{f}-z_{o})$ (1)

Where:

$m$ - Mass, measured in kilograms.

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

$z_{o}$ , $z_{f}$ - Initial and final height with respect to zero reference, measured in meters.

Please notice that $m\cdot g$ is the weight of the particle, measured in newtons.

a) If we know that $m = 3\,kg$ , $g = 9.807\,\frac{m}{s^{2}}$ , $z_{o} = 0\,m$ and $z_{f} = 4.1\,m$ , then the change in potential energy is:

$\Delta U_{g} = (3\,kg)\cdot \left(9.807\,\frac{m}{s^{2}} \right)\cdot (4.1\,m-0\,m)$

$\Delta U_{g} = 120.626\,J$

The change in potential energy of a 3.0 kilograms backpack carried up the stairs.

b) If we know that $m\cdot g = 650\,N$ , $z_{o} = 4.1\,m$ and $z_{f} = 0\,m$ , then the change in potential energy is:

$\Delta U_{g} = (650\,N)\cdot (0\,m-4.1\,m)$

$\Delta U_{g} = -2665\,J$

The change in potential energy of a persona with weight 650 newtons that descends the stairs is -2665 joules.

5 0

3 years ago