Ask question

Ask question

All categories

3 years ago

15

Bird bones have air pockets in them to reduce their weight—this also gives them an average density significantly less thanthat o

f the bones of other animals. Suppose an ornithologist weighs a bird bone in air and in water and ﬁnds its mass is45.0 g and its apparent mass when submerged is 3.60 g (the bone is watertight). (a) What mass of water is displaced? (b)What is the volume of the bone? (c) What is its average densim

1 answer:

snow_tiger [21]3 years ago

3 0

Answer:

41.4 g

41.4 cm³

1.08695 g/cm³

Explanation:

$\rho$ = Density of water = 1 g/cm³

Mass of water displaced will be the difference of the

$m=45-3.6\\\Rightarrow m=41.4\ g$

Mass of water displaced is 41.4 g

Density is given by

$\rho=\dfrac{m}{v}\\\Rightarrow v=\dfrac{m}{\rho}\\\Rightarrow v=\dfrac{41.4}{1}\\\Rightarrow v=41.4\ cm^3$

So, volume of bone is 41.4 cm³

Average density of the bird is given by

$\rho=\dfrac{45}{41.4}\\\Rightarrow \rho=1.08695\ g/cm^3$

The average density is 1.08695 g/cm³

You might be interested in

What are four pieces of evidence for continental drift?

Tomtit [17]

continents, paleoclimate indicators, truncated geologic features, and fossils:D

5 0

3 years ago

Read 2 more answers

an electric current 0.75 a passes through a circuit that has a resistance of 175. according to ohm's law, what is the voltage of

Aleksandr [31]

Answer:

131.25

Explanation:

i worked it out on a diffrent sheet so its hard to explain

8 0

2 years ago

In an LC circuit at one time the charge stored by the capacitor is 10 mC and the current is 3.0 A. If the frequency of the circu

Ronch [10]

Answer:

$i_2=3.61\ A$

Explanation:

<u>LC Circuit</u>

It's a special circuit made of three basic elements: The AC source, a capacitor, and an inductor. The charge, current, and voltage are oscillating when there is an interaction between the electric and magnetic fields of the elements. The following variables will be used for the formulas:

$q, q_1, q_2$ = charge of the capacitor in any time $t, t_1, t_2$

$q_o$ = initial charge of the capacitor

$\omega$ =angular frequency of the circuit

$i, i_1, i_2$ = current through the circuit in any time $t, t_1, t_2$

The charge in an LC circuit is given by

$q(t) = q_0 \, cos (\omega t )$

The current is the derivative of the charge

$\displaystyle i(t) = \frac{dq(t)}{dt} = - \omega q_0 \, sin(\omega t).$

We are given

$q_1=10\ mc=0.01\ c, i_1=3\ A,\ q_2=6\ mc=0.006\ c\ ,\ f=\frac{1000}{4\pi}$

It means that

$q(t_1) = q_0 \, cos (\omega t_1 )=q_1\ .......[eq 1]$

$i(t_1) = - \omega q_0 \, sin(\omega t_1)=i_1.........[eq 2]$

From eq 1:

$\displaystyle cos (\omega t_1 )=\frac{q_1}{q_0}$

From eq 2:

$\displaystyle sin(\omega t_1)=-\frac{i_1}{\omega q_0}$

Squaring and adding the last two equations, and knowing that

$sin^2x+cos^2x=1$

$\displaystyle \left ( \frac{q_1}{q_0} \right )^2+\left ( \frac{i_1}{\omega q_0} \right )^2=1$

Operating

$\displaystyle \omega^2q_1^2+i_1^2=\omega^2q_o^2$

Solving for $q_o$

$\displaystyle q_o=\frac{\sqrt{\omega^2q_1^2+i_1^2}}{\omega}$

Now we know the value of $q_0$ , we repeat the procedure of eq 1 and eq 2, but now at the second time $t_2$ , and solve for $i_2$

$\displaystyle \omega^2q_2^2+i_2^2=\omega^2q_o^2$

Solving for $i_2$

$\displaystyle i_2=w\sqrt{q_o^2-q_2^2}$

Now we replace the given values. We'll assume that the placeholder is a pi for the frequency, i.e.

$\displaystyle f=\frac{1}{4\pi}\ KHz$

$w=2\pi f=500\ rad/s$

$\displaystyle q_o=\frac{\sqrt{(500)^2(0.01)^2+3^2}}{500}$

$q_0=0.01166\ c$

Finally

$\displaystyle i_2=500\sqrt{0.01166^2-.006^2}$

$i_2=5\ A$

3 0

3 years ago

The mass of a string is 7.7 × 10-3 kg, and it is stretched so that the tension in it is 190 N. A transverse wave traveling on th

Scilla [17]

Length of the strings = 2.33 m

3 0

2 years ago

Match the terms to the correct descriptions.

LenaWriter [7]

1. Energy Conversion

2. Light Energy

3. Mechanical Energy

4. Kinetic Energy

5. Potential Energy

6. Sound Energy

7. Electrical Energy

8. Chemical Energy

9. Thermal Energy

10. Nuclear energy

Hope that helps u!

:)

8 0

3 years ago