If the wavelength is 10 m and the frequency is 5 Hz, what is the wave speed?

What is the mass of 3 m3 of a substance having density 1200 kg/m3

adell [148]

Answer:

3600 kg

Explanation:

From the question,

Density = Mass/Volume

D = M/V.............................. Equation 1

Where D = Density of the substance, M = mass of the substance, V = Volume of the subtance.

Make M the subject of the equation

M = D×V ............................ Equation 2

Given: D = 1200 kg/m³, V = 3 m³.

Substitute these values into equation 2

M = 1200×3

M = 3600 kg.

Hence the mass of the substance is 3600 kg

4 0

2 years ago

A 3.50-meter length of wire with a cross-sectional area of 3.14 × 10-6 meter2 is at 20° Celsius. If the wire has a resistance of

maks197457 [2]

Answer:

$5.6\times 10^{-8}\ Ohm.m$

Explanation:

Resistivity is given by $\rho=\frac {AR}{L}$ where A is cross-sectional area, R is resistance, L is the length and $\rho$ is the reistivity. Substituting 0.0625 for R, 3.14 × 10-6 for A and 3.5 m for L then the resistivity is equivalent to

$\rho=\frac {3.14\times 10^{-6}\times 0.0625}{3.5}=5.60714285714285714285714285714285714285\times 10^{-8}\approx 5.6\times 10^{-8}\ Ohm.m$

8 0

3 years ago

A 5.0-μC charge is placed at the 0 cm mark of a meter stick and a -4.0 μC charge is placed at the 50 cm mark. At what point on a

Maksim231197 [3]

Answer:

The distance from charge 5 μ C = 26.45 cm and the distance from - 4 μ C is 23.55 cm.

Explanation:

Given that

q₁ = 5 μ C

q₂ = - 4 μ C

The distance between charges = 50 cm

d= 50 cm

Lets take at distance x from the charge μ C ,the electrical field is zero.

That is why the distance from the charge - 4 μ C = 50 - x cm

We know that ,electric field is given as

$E=K\dfrac{q}{r^2}$

$K\dfrac{5\ \mu}{x^2}=K\dfrac{4\mu }{(50-x)^2}\\\\\dfrac{5}{x^2}=\dfrac{4 }{(50-x)^2}\\\\\\5(50-x)^2=4x^2\\(50-x)^2=0.8x^2\\\\50-x =0.89x\\\ x=\dfrac{50}{1.89}\ cm\\\\\\x=26.45\ cm\\$

Therefore the distance from charge 5 μ C = 26.45 cm and the distance from - 4 μ C is 23.55 cm.

3 0

3 years ago

In the system illustrated by the diagram, the magnetic field is increasing. In which

Black_prince [1.1K]

The emf will be induced in anti-clockwise direction.

<u>Explanation</u>

Lenz's law tells us the direction us the direction that the current will flow. It states that the direction is always such that it will oppose the change in flux which produced it. This means that any magnetic field produced by an induced current will be in opposite direction to the change in the original field.

To find the direction of emf, Stretch the forefinger, middle finger and the thumb of the right hand mutually perpendicular to each other. If the force finger points in the direction of the magnetic field, the thumb gives the direction of the motion of the conductor then the middle finger gives the direction of the induced current.

3 0

3 years ago

Which of these ionic compounds have polyatomic ions? Check all that apply.

Taya2010 [7]

Answer:

CaCO₃ and
NaOH.

Explanation:

Polyatomic ions are ions that contain more than one atom in each one of the ions.

Ionic compounds are made of cations (positive ions) and anions (negative ion). By convention, the cation is written before the anion.

List the ions in each compound:

Cation: $\rm Ca^{2+}$ ,

Anion: $\rm {CO_3}^{2-}$ .

$\rm Ca^{2+}$ is a monatomic ion for it contains only one atom in each ion.

$\rm {CO_3}^{2-}$ is a polyatomic ion for it contains four atoms (one C atom and three O atoms) in each ion.

Cation: $\rm Na^{+}$ ,

Anion: $\rm F^{-}$ .

Both $\rm Na^{+}$ and $\rm F^{-}$ are monatomic for they contain only one atom in each ion.

Cation: $\rm Fe^{2+}$ ,

Anion: $\rm {O}^{2-}$ .

Both $\rm Fe^{2+}$ and $\rm O^{2-}$ are monatomic for they contain only one atom in each ion.

Cation: $\rm Ca^{2+}$ ,

Anion: $\rm {Cl}^{-}$ .

Both $\rm Ca^{2+}$ and $\rm Cl^{-}$ are monatomic for they contain only one atom in each ion.

Cation: $\rm Na^{+}$ ,

Anion: $\rm {OH}^{-}$ .

$\rm Na^{+}$ is a monatomic ion for it contains only one atom in each ion.

$\rm {OH}^{-}$ is a polyatomic ion for it contains two atoms (one O atom and one H atom) in each ion.

5 0

2 years ago

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