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2 years ago

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A certain satellite has a kinetic energy of 7.5 billion joules at perigee (closest to Earth) and 6.5 billion joules at apogee (f

arthest from Earth). As the satellite travels from apogee to perigee, how much work does the gravitational force do on it?

1 answer:

Elena L [17]2 years ago

8 0

Answer:

Work Done by the earth's gravitational force on the satellite as it travels from apogee to perigee is

W = F*D*Cos90° = 0

Explanation:

Although there is a change in the kinetic energy of the satellite at the apogee and perigee, the work done by the earth's gravitational force on the satellite is Zero.

W = F.D, F is the gravitational force, D is the displacement. Both F and D are vectors and perpendicular to each other. That is, the angle between F and D is 90°.

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If the charge that enters each meter of the axon gets distributed uniformly along it, how many coulombs of charge enter a 0.100

SCORPION-xisa [38]

Answer:

Charge enter a 0.100 mm length of the axon is $8.98\times 10^{-12} C$

Explanation:

Electric field E at a point due to a point charge is given by

$E=k \frac{q}{r^2}$

where $k$ is the constant = $9.0 \times 10^9 Nm^2 / C^2$

$q$ is the magnitude of point charge and $r$ is the distance from the point charge

Charges entering one meter of axon is $5.\times 10^{11} \times (+e)$

Charges entering 0.100 mm of axon is $5.\times 10^{11} \times (+e) \times (0.1 \times 10^{-3}$

substituting the value of $+e=1.6\times 10^{-19} C$ in above equation, we get charge enter a 0.100 mm length of the axon is

$q=5.\times 10^{11} \times1.6\times 10^{-19} \times (0.1 \times 10^{-3}\\q=8.98\times 10^{-12} C$

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2 years ago

The acceleration of an object as a function of time is given by a(t) = (1.00 m/s2)t2. If displacement of the object between time

jolli1 [7]

not enough information is given to determine the velocity of the object at time to=0.00s

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2 years ago

A jet engine gets its thrust by taking in air, heating and compressing it, and

nadya68 [22]

Answer:

$F=ma=20\ Kg\ 400\ m/s^2=8,000\ Nw$

Explanation:

Thrust is known as a reaction force which appears when a system expels or accelerates mass in one specific direction. If we know the acceleration and the mass of the air expelled by the jet engine, we can compute the thrust .

The acceleration is calculated by using the dynamics formula

$\displaystyle a=\frac{v_f-v_o}{t}$

The values are

$v_f=500\ m/s,\ v_o=100\ m/s,\ t=1\ sec$

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The thrust is

$F=ma=20\ Kg\ 400\ m/s^2=8,000\ Nw$

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2 years ago

A wooden piece is made in different shapes take length (l) = radius (r) = 2m Calculate its volume as a:

In-s [12.5K]

This question deals with the volume of different shapes.

a) volume of the sphere is "33.51 m³".

b) volume of the cylinder is "25.13 m³".

a)

The volume of a sphere is given by the following formula:

$Volume = \frac{4}{3}\pi r^3\\\\Volume = \frac{4}{3}\pi (2\ m)^3$

<u>Volume = 33.51 m³</u>

<u />

b)

The volume of a cylinder is given by the following formula:

$Volume = \pi r^2l\\\\Volume =\pi (2\ m)^2(2\ m)$

<u>Volume = 25.13 m³</u>

<u />

Learn more about <em>volume </em>here:

brainly.com/question/16686115?referrer=searchResults

The attached picture shows the formulae of the <em>volume</em> of different shapes.

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2 years ago

When boiling water, a hot plate takes an average of 8 minutes and 55 seconds to boil 100 milliliters of water. Assume the temper

alexandr1967 [171]

Answer:

90.9 seconds

Explanation:

m = Mass of liquid = Volume×Density

c = Specific heat

$\Delta T$ = Change in temperature

t = Time taken

Room temperature = 75 °F

Converting to Celsius

$(75-32)\times \frac{5}{9}=23.889\ ^{\circ}C$

Heat required to raise the temperature of water

$Q=mc\Delta T\\\Rightarrow Q=100\times 10^{-6}\times 1000\times 4186\times (100-23.889)\\\Rightarrow Q=31860.0646\ J$

Power

$P=\frac{Q}{t}\\\Rightarrow P=\frac{31860.0646}{8\times 60+55}\\\Rightarrow P=59.55152\ W$

Efficiency of the plate

$\frac{59.5512}{283}\times 100=21.04282\%$

Heat required to raise the temperature of water

$Q=mc\Delta T\\\Rightarrow Q=100\times 10^{-6}\times 784\times 2150\times (56-23.889)\\\Rightarrow Q=5412.63016\ J$

$P=\frac{Q}{t}\\\Rightarrow t=\frac{Q}{P}\\\Rightarrow t=\frac{5412.63016}{0.2104282\times 283}\\\Rightarrow t=90.9\ s$

Time taken to heat the aceton is 90.9 seconds

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2 years ago