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3 years ago

What is escape velocity

1 answer:

8 0

Escape velocity is the speed that an object needs to be traveling to break free of a planet or moon's gravity well and leave it without further propulsion. For example, a spacecraft leaving the surface of Earth needs to be going 7 miles per second, or nearly 25,000 miles per hour to leave without falling back to the surface or falling into orbit.

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Ground reaction force acting on carter

mezya [45]

We don't know Carter, and we don't know where he is or what
he's doing, so I'm taking a big chance speculating on an answer.

I'm going to say that if Carter is pretty much just standing there,
or, let's say, lying on the ground taking a nap, then the force of
the ground acting on him is precisely exactly equal to his weight.

8 0

3 years ago

Why do hot stars look bluer than cool stars?

brilliants [131]

Answer:

(B) The wavelength that a star radiates the most energy is inversely proportional to the temperature.

Explanation:

As we know that

According to Wien's law wavelength is inverse proportional to the temperature .

λ.T = Constant.

λ.∝ 1 /T

As we know that star radiates wavelength and this wavelength is inverse proportional to the temperature of the star.

The temperature of cool star is cooler than the temperature of hot star that is cool star looks red and hot star looks blue.Cool star have low energy and hot star have high energy.

So option B is correct.

(B) The wavelength that a star radiates the most energy is inversely proportional to the temperature.

5 0

3 years ago

A gas exerts less pressure when it has a

Vika [28.1K]

The molecules are continually colliding with each other and with the walls of the container. When a molecule collides with the wall, they exert small force on the wall The pressure exerted by the gas is due to the sum of all these collision forces.The more particles that hit the walls, the higher the pressure.

4 0

3 years ago

A 4 kW vacuum cleaner is powered by an electric motor whose efficiency is 90%. (Note that the electric motor delivers 4 W of net

RoseWind [281]

Answer: $3.6\ kW$

Explanation:

Given

Power Supplied $[tex]P_{input}=4\ kW$ [/tex]

Efficiency of the motor $\neta =90\%$

and $\neta =\dfrac{\text{Power output}}{\text{Power input}}$

$\Rightarrow 0.9=\dfrac{P_{out}}{4}$

$\Rightarrow P=0.9\times 4$

$\Rightarrow P=3.6\ kW$

So, vacuum cleaner delivers a power of $3.6\ kW$

3 0

3 years ago

An exoplanet with one half of Earth's mass and 50% of Earth's radius is discovered.

Georgia [21]

Answer:

The space cadet that weighs 800 N on Earth will weigh 1,600 N on the exoplanet

Explanation:

The given parameters are;

The mass of the exoplanet = 1/2×The mass of the Earth, M = 1/2 × M

The radius of the exoplanet = 50% of the radius of the Earth = 1/2 × The Earth's radius, R = 50/100 × R = 1/2 × R

The weight of the cadet on Earth = 800 N

$The \ weight, W =G\dfrac{M \times m}{R^{2}} = 800 \ N$

Therefore, for the weight of the cadet on the exoplanet, W₁, we have;

$W_1 =G\dfrac{\dfrac{M}{2} \times m}{ \left ( \dfrac{R}{2} \right ) ^{2}} = G\dfrac{\dfrac{M}{2} \times m \times 4}{ R ^{2}} = 2 \times G \times \dfrac{M \times m}{R^{2}} = 2 \times 800 \, N = 1,600 \, N$

The weight of a space cadet on the exoplanet, that weighs 800 N on Earth = 1,600 N.

7 0

3 years ago

What is escape velocity ​

What is escape velocity