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3 years ago

How did Galileo's observations of Jupiter and Venus support Copernicus's model?

1 answer:

7 0

Before Copernicus most people were thinking that the Earth is at center of universe. In 1609 Galileo observed sky through his home made telescope.
He found 4 moons orbiting Jupiter..It was a proof that bodies are orbiting other planets and not earth alone. <span>He found the crescent shape of Venus through his telescope and this could happen only if Sun is at center.</span>

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Please help!!!!!!!!!

IgorC [24]

In an Internal Combustion Engine, the fuel is singed in the chamber or vessel. Example: Diesel or Petrol motor utilized as a part of Cars.
The internal engine has its vitality touched off in the barrel, as 99.9% of motors today. In an External Combustion Engine, the inner working fuel is not consumed. Here the liquid is being warmed from an outer source. The fuel is warmed and extended through the interior instrument of the motor bringing about work. Eg. Steam Turbine, Steam motor Trains. An outer burning case is a steam motor where the warming procedure is done in a kettle outside the motor.

5 0

3 years ago

When the play button is pressed, a CD accelerates uniformly from rest to 450 rev/min in 3.0 revolutions. If the CD has a radius

Marina CMI [18]

To solve this problem it is necessary to apply the kinematic equations of angular motion.

Torque from the rotational movement is defined as

$\tau = I\alpha$

where

I = Moment of inertia $\rightarrow \frac{1}{2}mr^2$ For a disk

$\alpha =$ Angular acceleration

The angular acceleration at the same time can be defined as function of angular velocity and angular displacement (Without considering time) through the expression:

$2 \alpha \theta = \omega_f^2-\omega_i^2$

Where

$\omega_{f,i} =$ Final and Initial Angular velocity

$\alpha =$ Angular acceleration

$\theta =$ Angular displacement

Our values are given as

$\omega_i = 0 rad/s$

$\omega_f = 450rev/min (\frac{1min}{60s})(\frac{2\pi rad}{1rev})$

$\omega_f = 47.12rad/s$

$\theta = 3 rev (\frac{2\pi rad}{1rev}) \rightarrow 6\pi rad$

$r = 7cm = 7*10^{-2}m$

$m = 17g = 17*10^{-3}kg$

Using the expression of angular acceleration we can find the to then find the torque, that is,

$2\alpha\theta=\omega_f^2-\omega_i^2$

$\alpha=\frac{\omega_f^2-\omega_i^2}{2\theta}$

$\alpha = \frac{47.12^2-0^2}{2*6\pi}$

$\alpha = 58.89rad/s^2$

With the expression of the acceleration found it is now necessary to replace it on the torque equation and the respective moment of inertia for the disk, so

$\tau = I\alpha$

$\tau = (\frac{1}{2}mr^2)\alpha$

$\tau = (\frac{1}{2}(17*10^{-3})(7*10^{-2})^2)(58.89)$

$\tau = 0.00245N\cdot m \approx 2.45*10^{-3}N\cdot m$

Therefore the torque exerted on it is $2.45*10^{-3}N\cdot m$

3 0

3 years ago

Which equations could be used as is, or rearranged to calculate for frequency of a wave? Check all that apply.

amm1812

-- Equations #2 and #6 are both the same equation,
and are both correct.

-- If you divide each side by 'wavelength', you get Equation #4,
which is also correct.

-- If you divide each side by 'frequency', you get Equation #3,
which is also correct.
With some work, you can rearrange this one and use it to calculate
frequency.

Summary:

-- Equations #2, #3, #4, and #6 are all correct statements,
and can be used to find frequency.

-- Equations #1 and #5 are incorrect statements.

7 0

3 years ago

Read 2 more answers

How to convert 40m/min to km/h? need step by step explanation

Hitman42 [59]

Answer:

i have no clue i just need brailnly points

Explanation:

7 0

3 years ago

Read 2 more answers

An AC source is connected to a series combination of a light bulb and a variable capacitor. If the capacitance is increased, the

notsponge [240]

Answer:

Increases

Explanation:

Since power P=IV

Then it means when current increases, the power increases hence brightness increases. I represent current, P is power and v is voltage.

Current of capacitor when in series connection is given by

$I=2\pi fCV$

where I is current across capacitor, f is frequency, C is capacitance and v is voltage across capacitance. From this second formula, it is evident that an increase in capacitance increases the current across the capacitor. Therefore, if current increases, power also increases leading to an increase in brightness

3 0

3 years ago