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3 years ago

Edwin Hubble discovered that:

Physics

1 answer:

Novosadov [1.4K]3 years ago

3 0

Answer:

galaxies were moving away from us

Explanation:

i got 100% on my quiz

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A 30 g particle is undergoing simple harmonic motion with an amplitude of 2.0 ✕ 10-3 m and a maximum acceleration of magnitude 8

KiRa [710]

Answer:

Explanation:

By using the Newton second law and the position equation for a simple harmonic motion we have

$F=ma\\a_{max}=\omega^{2}A\\x=Acos(\omega t+ \phi)\\$

where a is the acceleration, w is the angular frecuency and \phi is the phase constant. We can calculate w from the equation for the maximum acceleration

$\omega=\sqrt{\frac{a_{max}}{A}}=\sqrt{\frac{8*10^{3}m/s^{2}}{2*10^{-3}}}=2000rad/s$

(a).

$F=ma=m\omega^{2}Acos(\omega t + \phi)\\F=(30*10^{-3}kg)(2*10^{-3}m)(2000\frac{rad}{s})^{2}cos(2000\frac{rad}{s} t - \frac{\pi}{2})=240N*cos(2000\frac{rad}{s} t - \frac{\pi}{2})$

(b). $T=\frac{2\pi}{\omega}=\frac{2\pi}{2000}=3.14*10^{-13} s$

(c). $v_{max}=A\omega=(2*10^{-3}m)(2000\frac{rad}{s})=4\frac{m}{s}$

(d). The mecanical energy is the kinetic energy when the velocity is a maximum

$E_{m}=E_{k}(v_{max})=\frac{mv_{max}^{2}}{2}=\frac{30*10^{-3}kg(4\frac{m}{s})^{2}}{2}=0.024J$

3 0

4 years ago

Read 2 more answers

A roller-coaster car has a mass of 1080 kg when fully loaded with passengers. As the car passes over the top of a circular hill

Dmitriy789 [7]

Answer:

(a): The normal force on the car from the track when the car's speed is v= 7.6 m/s is FN= -6696 N.

(b): The normal force on the car from the track when the car's speed is v= 17 m/s is FN= 8912.7 N.

Explanation:

m= 1080 kg

r= 16m

v1= 7.6 m/s

v2= 17 m/s

g= 9.81 m/s²

v1= w1*r

w1= v1/r

w1= 0.475 rad/s

ac1= w1² * r

ac1= 3.61 m/s²

FN= m * (ac1 - g)

FN= -6696 N (a)

-----------------------------------------------------

v2= w2*r

w2= v2/r

w2= 1.06 rad/s

ac2= w2² * r

ac2= 18.06 m/s²

FN= m * (ac2 - g)

FN= 8912.7 N (b)

4 0

3 years ago

Select the correct answer. Samuel adds a teaspoon of salt to a glass of water. He notices that the salt disappears. Samuel takes

borishaifa [10]

Answer:

Explanation:

A chemical reaction is a process that leads to the chemical transformation of one set of chemical substances to another. Therefore it can not be any of the other answers because the substance was water at first but now its salty water.

ps what kind of person would drink water after you put salt in it lol.

8 0

3 years ago

After a collision, the y-component of momentum of a car is 4.50 meters/second, and the x-component of its momentum is 9.80 meter

Natalka [10]

The components are at a right angle so the resultant is R^2 = 4.50^2 + 9.80^2 R = 10.78 or 10.8

Hope this helps!!
~Lena~

5 0

3 years ago

URGENT HELP!

Inga [223]

1) The forces of molecules is how strong they are being held together. Now, we know that solid is the last one, because it's particles are held CLOSELY and VERY TIGHTLY together, which is why it has a definite shape.And last of all, a gas's particles are held freely, which is why it has no shape. So the answer would be:- gas, liquid, solid

3) The state of matter that does not have a definite shape, but has a definite volume is a liquid. So the answer is :- liquid

7) False, an endothermic reaction is when it absorbs energy, and as we know that in a chemical reaction as the following, it tends to be an exothermic reaction, meaning that is releases energy. So the answer is:- FALSE

8) Gases have particles that are far apart (freely) and move fast. So the answer is:- They are moving very fast and are far apart.<span> </span>

6 0

3 years ago

Read 2 more answers