Explanation:
using the first eqn for motion
Answer:
350.72 m/s
Explanation:
Formula for velocity of wave is;
v = fλ
Where;
v is speed
f is frequency
λ is wavelength
We are given;
f = 512 Hz
λ = 0.685 m
Thus;
v = 512 × 0.685
v = 350.72 m/s
Answer:
The steam will start to condense at 6.6 mm into the pipe
Explanation:
The volume flow rate =π×(50/1000)²/4×10 = 0.0196 m³/s
The specific volume of the steam = 1.769 m³/kg
Therefore;
The mass flow rate = 0.0196/1.769 = 0.011099 kg/s
The resistance of the insulation material = ln(0.075/0.05)/(2×π×0.075) = 0.860 K/W
The resistance of the outside film of the insulator = 1/(15×2×π×0.075×1) = 0.14147 K/W
The total resistance = 0.14147 + 0.860 = 1.00147 K/W
1/(UA) = 1.00147 K/W
A = 2×π×0.05×1
1/U = 0.3146
U = 3.178 W/m² K
We have;
T(x) = T₀ + (Tin - T₀) exp(-UπDx/mcp)
Therefore, when T(x) = 100°C, we have;
100 = 20 + (120 - 20)exp(-3.178×π×0.05x/(0.011099 × 1.33))
Solving, we get
x = 6.597× 10⁻³ m ≈ 6.6 mm
Therefore, the steam will start to condense at 10 mm into the pipe.
Well, first of all, you really shouldn't use ' W ' for the unit when you
talk about resistors.
You may have seen the resistors written as 6ω, 12ω, and 2ω in your
book or on the homework sheet. But that little symbol ' ω ' is not a ' w '.
It's the small Greek letter 'omega'. The CAPITAL omega is ' Ω '. It's used
to label resistors because it's short for "ohms". So the resistors in this
problem have resistances of 6Ω, 12Ω, and 2Ω, and we have to do some
manipulating of the individual resistors to find out what resistance the
battery actually sees.
The parallel combination of the first two resistors looks like a single
resistor, whose value is
1 / (1/6 + 1/12)
= 1 / (2/12 + 1/12)
= 1 / (3/12)
= 12/3 = 4Ω .
Now, that parallel combination is connected in series with 2Ω .
All three resistors together look like a single resistor of
4Ω + 2Ω = 6Ω .
So the battery thinks there's a single resistor connected to it,
with 6Ω of resistance. The current out of the battery is
I = V / R = (24v) / (6Ω) = 4 Amperes.
That 4 Amperes of current will split between the parallel resistors,
but it will ALL flow through the series 2Ω resistor because there's
no other path through that part of the circuit.
So the current through the 2Ω resistor is 4 Amperes. (B).
Note:
The POWER dissipated by the 2Ω resistor is
P = I² R = (4A)² · (2Ω) = 32 watts .
This is a fair amount of heat, so you'll need to provide some way
to remove the heat from the resistor, otherwise it'll burn or crack.
Answer:
negative ion
Explanation:
An atom that has fewer neutrons than protons and more electrons than protons is a negative ion.
The positively charged particles in an atom are the protons
The negatively charged particles in an atom are the electrons.
The charge an atom carries depends on the balance between the number of protons and electrons in an atom.
- When the number of protons is more than the number of electrons, the atom is positively charged.
- When the number of electrons is more than the number of protons, the atom is negatively charged.
