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3 years ago

Compare the foot of mollusks with the tube feet of echinoderms.

Physics

1 answer:

stira [4]3 years ago

4 0

Mollusks live in fresh water, in marine environment, but also on land.

<span>Echinoderms live only in water. This is the reason why they have developed different systems for moving. Mollusks have only singular muskullus foot for walking and Echinoderms have tube feet which they use for moving, as well for collecting and transporting food to their mouth. </span>

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Jupiter's moon Io has active volcanoes (in fact, it is the most volcanically active body in the solar system) that eject materia

Anton [14]

Answer:

91.64 km

91.64 km high material would go on earth if it were ejected with the same speed as on Io.

Explanation:

According to Newton Law of gravitation:

$g=\frac{Gm}{r^2}$

Where:

G is gravitational constant= $6.67*10^{-11} m^3/kg.s^2$

For Moon lo g is:

$g_M=\frac{6.67*10^{-11}*8.93*10^{22}}{(1821*10^3)^2m^2} \\g_M=1.7962 m/s^2$

According to law of conservation of energy

Initial Energy=Final Energy

$K.E_i+mgh_i=K.E_f+mgh_f$

$\frac{1}{2}m(v_0)^2+mgh_o= \frac{1}{2}m(v_f)^2+mgh_f\\At\ maximum\ height\ v_f=0\\\frac{1}{2}m(v_0)^2+0=mgh_f\\v_0=\sqrt{2gh_f}$

For Jupiter's moon Io:

Velocity is given by:

$v_0_M=\sqrt{2g_Mh_f_M}$

For Earth Velocity is given by:

$v_0_E=\sqrt{2g_Eh_f_E}$

Now:

$v_o_M=v_o_E$

$\sqrt{2g_Mh_f_M}=\sqrt{2g_Eh_f_E}\\h_f_E=\frac{g_Mh_f_M}{g_E}$

$g_E=9.8 m/s^2$

$g_m=1.7962 m/s^2, As\ Calculated\ above$

$h_f_E=\frac{1.7962*500*10^3m}{9.8} \\h_f_E=91642.85 m\\h_f_E=91.64Km$

91.64 km high material would go on earth if it were ejected with the same speed as on Io.

8 0

3 years ago

Force F = (-6.0 N)ihat + (2.0 N) jhatacts on a particle with position vector r =(4.0 m) ihat+ (4.0 m) jhat.

finlep [7]

Answer:

$\tau=(-32k)\ N-m$

$\theta=116.55^{\circ}$

Explanation:

Given that.

Force acting on the particle, $F=(-6i + 2.0j)\ N$

Position of the particle, $r=(4i+4j)\ m$

To find,

(a) Torque on the particle about the origin.

(b) The angle between the directions of r and F

Solution,

(a) Torque acting on the particle is a scalar quantity. It is given by the cross product of force and position. It is given by :

$\tau=F\times r$

$\tau=(-6i + 2.0j)\times (4i+4j)$

$\tau=\begin{pmatrix}0&0&-32\end{pmatrix}$

$\tau=(-32k)\ N-m$

So, the torque on the particle about the origin is (32 N-m).

(b) Magnitude of r, $|r|=\sqrt{4^2+4^2}=5.65\ m$

Magnitude of F, $|F|=\sqrt{(-6)^2+2^2}=6.324\ m$

Using dot product formula,

$F{\circ}\ r=|F|.|r|\ cos\theta$

$cos\theta=\dfrac{F{\circ} r}{|F|.|r|}$

$cos\theta=\dfrac{-24+8}{6.324\times 5.65}$

$\theta=116.55^{\circ}$

Therefore, this is the required solution.

6 0

3 years ago

Read 2 more answers

Acceleration = change of velocity divided by time interval = Δv/Δt.

MariettaO [177]

Answer:

a=2.378 m/s^2

Explanation:

a=Δv/Δt------eq(1)

Δv=Vf-Vi=120 km/h-0 km/h=120 km/h

or Δv=33.3 m/sec

or time=t=14s

putting values in eq(1)

a=33.3/14

a=2.378 m/s^2

6 0

3 years ago

Which of the following is a type of natural disaster that has impacted Florida? A. Avalanche B. Flood C. Typhoon D. Volcano

snow_tiger [21]

Answer:

B-flood

Explanation:

The Sunshine State is famous all around the world for many great things but also is famous because of a big array of natural disasters.From hurricanes, tropical storms, tornadoes, to fires and floods many natural disasters in Florida affect the lives of residents.

7 0

3 years ago

Read 2 more answers

A star’s light is alternately shifted from the blue part of the light spectrum to the red part.

g100num [7]

The answer is A because it is an example of red shift which if basically the Doppler effect , but for light. The wavelength gets longer because it has visible light has shifted into the red end of the spectrum, showing that it has a shorter frequency with a longer wavelength; meaning it is moving away from us

4 0

3 years ago