All categories

3 years ago

Which water would you use to make salt dissolve the slowest?

Physics

1 answer:

harkovskaia [24]3 years ago

4 0

Answer:

boiling water because salt dissolves quicker in hot Water and the hottest is boiling

You might be interested in

A wall has inner and outer surface temperatures of 25◦C and 8◦C, respectively. The interior and exterior air temperatures are 35

Angelina_Jolie [31]

Answer:

a) $\frac{\dot Q}{A} =60\ W.m^{-2}$

b) $\frac{\dot Q}{A} =110\ W.m^{-2}$

c) The wall may not be under steady because the two surfaces of the wall are exposed to the air at different temperatures and they have different convective coefficient.

Explanation:

Given:

temperature of the inner surface of the wall, $T_i=25^{\circ}C$

temperature of the outer surface of the wall, $T_o=8^{\circ}C$

temperature of the air outside, $T_{ao}=-3^{\circ}C$

temperature of the air inside, $T_{ai}=35^{\circ}C$

coefficient of heat convection on outside, $h_o=10\ W.m^{-2}.K^{-1}$

coefficient of heat convection on inside, $h_i=6\ W.m^{-2}.K^{-1}$

The heat flux between the interior air and the wall:

The convective heat transfer rate is given as,

$Q=h_i.A.\Delta T$

$\Rightarrow \frac{\dot Q}{A} =h_i\times (T_{ai}-T_i)$

$\frac{\dot Q}{A} =6\times (35-25)$

$\frac{\dot Q}{A} =60\ W.m^{-2}$

The heat flux between the exterior air and the wall:

$\Rightarrow \frac{\dot Q}{A} =h_o\times (T_{ao}-T_i)$

$\frac{\dot Q}{A}=10\times (8-(-3))$

$\frac{\dot Q}{A} =110\ W.m^{-2}$

The wall may not be under steady because the two surfaces of the wall are exposed to the air at different temperatures and they have different convective coefficient.

4 0

4 years ago

Dave is moving 3 m/s when he crashes his bike into a wall, which stops him in 0.6 seconds. If Dave and his bike have a mass of 9

Arisa [49]

Force = change of momentum / time taken
Force = (90x3)/0.6

7 0

3 years ago

What is the advantage of adding more pulleys to a system of pulleys?

Citrus2011 [14]

You can pull more things at once

3 0

3 years ago

Calculate the work function that requires a 475 nm photon to eject an electron of 1.25 eV.

lapo4ka [179]

The work function has the formula
E = h v

where
E is the energy
h is the constant
v is the frequency

Since the given is wavelength, we use the relationship between frequency and wavelength
v = c / λ
where
c is the speed of light
<span>λ is the wavelength
</span>
So.
E = h c / <span>λ
h = E</span><span>λ / c = 1.25 eV (475x10-9m) / (3x10^8 m/s)
h = 1.9792 x 10^-15

The work function is:
E = 1.9792 x 10-15 v

</span>

3 0

3 years ago

10 po

NISA [10]

By the Newtons Second Law:

F = ma

F = (47 kg)(15 m/s²)

7 0

4 years ago