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2 years ago

Which of the following is evidence that the universe began with the big bang theory

1 answer:

6 0

<span>There are several main pieces of evidence that support the Big Bang theory. One is the fact that the universe is expanding, proven with something called red shift. The second is something called cosmic microwave background radiation. The third is the abundance of different elements in the universe.

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You might be interested in

What causes atoms to bond together<br> ?!?

lisov135 [29]

Answer:

electrostatic attraction

Explanation:

Atoms form chemical bonds with other atoms when there's an electrostatic attraction between them. This attraction results from the properties and characteristics of the atoms' outermost electrons, which are known as valence electrons.

7 0

3 years ago

Read 2 more answers

figure 2 shows a charged ball of mass m = 1.0 g and charage q = -24*10^-8 c suspended by massless string in the presence of a un

Vlad [161]

Answer:

E = 307667 N/C

Explanation:

Since the object's mass is 1 g, then its weight in newtons is 0.001 * 9.8 = 0.0098 N.

This weight should have the same magnitude of the vertical component of the tension T of the string (T * cos(37)) so we can find the magnitude of the tension T via:

0.0098 N = T * cos(37)

then T = 0.0098/cos(37) N = 0.01227 N

Knowing the tension's magnitude, we can find its horizontal component:

T * sin(37) = 0.007384 N

and now we can obtain the value of the electric field since we know the charge of the ball to be: -2.4 * 10^(-8) C:

0.007384 N = E * 2.4 * 10^(-8) C

Then E = 0.007384/2.4 * 10^(-8) N/C

E = 307667 N/C

8 0

3 years ago

A torque of 36.5 N · m is applied to an initially motionless wheel which rotates around a fixed axis. This torque is the result

vivado [14]

Answer:

$21.6\ \text{kg m}^2$

$3.672\ \text{Nm}$

$54.66\ \text{revolutions}$

Explanation:

$\tau$ = Torque = 36.5 Nm

$\omega_i$ = Initial angular velocity = 0

$\omega_f$ = Final angular velocity = 10.3 rad/s

t = Time = 6.1 s

I = Moment of inertia

From the kinematic equations of linear motion we have

$\omega_f=\omega_i+\alpha_1 t\\\Rightarrow \alpha_1=\dfrac{\omega_f-\omega_i}{t}\\\Rightarrow \alpha_1=\dfrac{10.3-0}{6.1}\\\Rightarrow \alpha_1=1.69\ \text{rad/s}^2$

Torque is given by

$\tau=I\alpha_1\\\Rightarrow I=\dfrac{\tau}{\alpha_1}\\\Rightarrow I=\dfrac{36.5}{1.69}\\\Rightarrow I=21.6\ \text{kg m}^2$

The wheel's moment of inertia is $21.6\ \text{kg m}^2$

t = 60.6 s

$\omega_i$ = 10.3 rad/s

$\omega_f$ = 0

$\alpha_2=\dfrac{0-10.3}{60.6}\\\Rightarrow \alpha_1=-0.17\ \text{rad/s}^2$

Frictional torque is given by

$\tau_f=I\alpha_2\\\Rightarrow \tau_f=21.6\times -0.17\\\Rightarrow \tau=-3.672\ \text{Nm}$

The magnitude of the torque caused by friction is $3.672\ \text{Nm}$

Speeding up

$\theta_1=0\times t+\dfrac{1}{2}\times 1.69\times 6.1^2\\\Rightarrow \theta_1=31.44\ \text{rad}$

Slowing down

$\theta_2=10.3\times 60.6+\dfrac{1}{2}\times (-0.17)\times 60.6^2\\\Rightarrow \theta_2=312.03\ \text{rad}$

Total number of revolutions

$\theta=\theta_1+\theta_2\\\Rightarrow \theta=31.44+312.03=343.47\ \text{rad}$

$\dfrac{343.47}{2\pi}=54.66\ \text{revolutions}$

The total number of revolutions the wheel goes through is $54.66\ \text{revolutions}$ .

3 0

2 years ago

A wave is traveling at 241 m/s. It has a wavelength of 30.0 m. What is its frequency?

Feliz [49]

Answer:

A) 8.03Hz

Explanation:

f = V/λ

Where wavelength( λ )= 30m

Speed (V) =241m/S

f= 241/30=8.03Hz

3 0

3 years ago

- A fridge has a maximum static friction force

Dennis_Churaev [7]

Answer:

They will move the fridge if they all push in the same direction, but it will not move with constant velocity

Explanation:

The maximum static friction force is

$F_f = -250 N$ (negative sign since its direction is opposite to the push applied by the people)

Sam can apply a force of 130 N, while Amir and Andre can apply a push of 65 N each, so the total force that they can apply, if they push in the same direction, will be:

$F=130 + 65 +65=260 N$

This force is larger than the frictional force, so the fridge will start moving.

However, the net force on the fridge will be:

$\sum F = 260 N - 250 N = 10 N$

And according to Newton's second law,

$\sum F = ma$

where m is the mass of the fridge and a its acceleration, since the net force is not zero, then the fridge will have a non-zero acceleration, so it will not move with constant velocity.

3 0

3 years ago