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2 years ago

Need help! Thanks for whoever answers.

Physics

2 answers:

kotegsom [21]2 years ago

7 0

Hi there!

Finding the time taken to land deals with the VERTICAL motion of the object, so we can disregard the horizontal velocity.

Use the simplified kinematic equation:

t = √2h/g

Plug in given values. Let g = 9.8 m/s²

t = √2(75)/9.8 = 3.91 sec

Hunter-Best [27]2 years ago

5 0

Answer:

2021 + 100000000

Explanation:

i o g kk ybb

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Astronomers have observed a small, massive object at the center of our Milky Way Galaxy. A ring of material orbits this massive

Setler [38]

Answer:

The mass of the massive object at the center of the Milky Way galaxy is $3.44\times10^{37}\ Kg$

Explanation:

Given that,

Diameter = 10 light year

Orbital speed = 180 km/s

Suppose determine the mass of the massive object at the center of the Milky Way galaxy.

Take the distance of one light year to be 9.461×10¹⁵ m. I was able to get this it is 4.26×10³⁷ kg.

We need to calculate the radius of the orbit

Using formula of radius

$r=\dfrac{d}{2}$

$r=\dfrac{15\times9.461\times10^{15}}{2}$

$r=7.09\times10^{16}\ m$

We need to calculate the mass of the massive object at the center of the Milky Way galaxy

Using formula of mass

$M=\dfrac{v^2r}{G}$

Put the value into the formula

$M=\dfrac{(180\times10^3)^2\times7.09\times10^{16}}{6.67\times10^{-11}}$

$M=3.44\times10^{37}\ Kg$

Hence, The mass of the massive object at the center of the Milky Way galaxy is $3.44\times10^{37}\ Kg$

5 0

2 years ago

A ball with a mass of 5 kg is accelerating at 5 m/s/s. What is the force acting on the ball?

Genrish500 [490]

Force is 25 N
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6 0

2 years ago

Read 2 more answers

Choose the scenario in which the sound frequency of the waves is higher.

mrs_skeptik [129]

Answer:

B) the sound source moves towards you at 100 m/sec

Explanation:

The Dopper Effect is a phenomenon that occur when there is relative motion between an observer and a source of a wave. When this situation occurs, there is an apparent shift in frequency of the wave, as observed by the observer.

The apparent frequency observed by the observer is given by

$f'=\frac{v\pm v_o}{v\pm v_s}f$

where

f is the original frequency of the wave

f' is the apparent frequency

v is the speed of the wave

$v_o$ is the velocity of the observer (positive if moving towards the source of the wave, negative otherwise)

$v_s$ is the velocity of the source (negative if moving towards from the observer, positive otherwise)

In this problem, we want to find the scenario in which the sound frequency is higher.

We see that in all 4 scenarios, the sound source is moving: this means we have to find the scenario in which the denominator of the equation is smaller.

First of all, we notice the sound source moves towards the observer, $v_s$ is negative, so the denominator is higher: this means that the correct option must be either A or B.

Also, we notice that since $v_s$ is negative, a value larger in magnitude will mean a smaller denominator: therefore, the correct answer will be

B) the sound source moves towards you at 100 m/sec

Since this situation will make the denominator of the formula the smallest possible.

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2 years ago

Exposure to a sufficient quantity of ultraviolet will redden the skin, producing erythema - a sunburn. The amount of exposure ne

ivann1987 [24]

Answer:

Energy = 7.83 x 10⁻¹⁹ J

Energy = 6.63 x 10⁻¹⁹ J

Explanation:

The energy of a photon in terms of wavelength can be calculated by the following formula:

$Energy = \frac{hc}{\lambda}\\$

where,

h = Plank's Constant = 6.63 x 10⁻³⁴ Js

c = speed of light = 3 x 10⁸ m/s

λ = wavelength of light

Now, for λ = 254 nm = 2.54 x 10⁻⁷ m:

$Energy = \frac{(6.63\ x\ 10^{-34}\ Js)(3\ x\ 10^8\ m/s)}{2.54\ x\ 10^{-7}\ m}\\$

Energy = 7.83 x 10⁻¹⁹ J

Now, for λ = 300 nm = 3 x 10⁻⁷ m:

$Energy = \frac{(6.63\ x\ 10^{-34}\ Js)(3\ x\ 10^8\ m/s)}{3\ x\ 10^{-7}\ m}\\$

Energy = 6.63 x 10⁻¹⁹ J

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2 years ago

How many neutrons does element X have if its atomic number is 22 and its mass number is 96?

Dovator [93]

1. The mass number is protons + neutrons = mass number. In this case, we have protons + neutron = 164.The atomic number is simply the number of protons so we have 43 + neutrons = 164. Subtracting 43 from both sides we get neutrons = 121.
2. = 4

3. The number of protons in the nucleus does not equal the number of neutrons.

A=mass number:
Z=atomic number (= number of protons)
N=number of neutrons:

A=Z+N

If the number of protons in the nucleus is equal the number of neutrons , we would have an even mass number; because Z=N=x; then A=x+x=2x (this is always an even number) but 23 is an odd number, therefore the number of protons in the nucleus does not equal the number of neutrons.

6 0

2 years ago