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tekilochka [14]

3 years ago

10

Though atomic physicists have made significant progress at understanding how God created the atom, a there is not yet a complete

understanding of all atomic interactions that exist.
True or False

1 answer:

MakcuM [25]3 years ago

7 0

True because it’s true

You might be interested in

42,43 and 44 please

Mariana [72]

42) The sailboat travels east with velocity $v_e=30 mph$ , while the current moves south with speed $v_s=30 mph$ . Since the two velocities are perpendicular to each other, he resultant velocity will be given by the Pytagorean theorem:
$v= \sqrt{v_e^2+v_s^2}= \sqrt{(30)^2+(30)^2}=42 mph$
and the direction is in between the two original directions, therefore south-east. So, the correct answer is
D) 42 mph southeast

43) Since the light moves by uniform motion, we can calculate the distance corresponding to one light year by using the basic relationship between velocity, space and time. In fact, we know the velocity:
$v=300,000,000 m/s=3 \cdot 10^8 m/s$
and the time is one year, corresponding to:
$t=32,000,000 s=3.2 \cdot 10^7 s$
therefore, the distance corresponding to one light year is:
$S=vt=(3\cdot 10^8 m/s)(3.2 \cdot 10^7 s)=9.6 \cdot 10^{15}m$
Therefore, the correct answer is D.

44) For the purpose of the problem, we can assume that the light travels instantaneously from the flash to us (because the distances involved are very small), so the time between the flash and the thunder corresponds to the time it took for the sound to travel to us.
The speed of sound is
$v=1100 ft/s=750 mph=335 m/s$
And since the time between the flash and the thunder is t=3 s, the distance is
$S=vt=(335 m/s)(3 s)=1005 m=0.62 miles$
Therefore, the correct answer is A) 3/5 mile.

6 0

3 years ago

Ksju [112]

1. False

Explanation: it's exactly the opposite. In fact, Lenz's law states that the induced current and the induced emf in a conductor are generated in such a direction that opposes to the change in magnetic flux through the coil. This is summarized by the negative sign in the Faraday's Newmann Lenz law:

$\epsilon= -\frac{d\Phi }{dt}$

where $\epsilon$ is the emf induced and $\frac{d\Phi}{dt}$ is the rate of change of magnetic flux through the coil.

Lenz's law is a consequence of the law of conservation of energy. In fact, we have:

- If the magnetic flux through a coil is increasing, then the induced current has a direction such that the magnetic field generated by the coil is opposite to the direction of the external magnetic field, in order to decrease the total flux

- If the magnetic flux through a coil is decreasing, then the induced current has a direction such that the magnetic field generated by the coil is in the same direction as the external field, in order to increase the total flux

2. False

Explanation: the magnetic flux through a surface is given by

$\Phi = BA cos \theta$

where

B is the magnitude of the magnetic field

A is the surface area

$\theta$ is the angle between the direction of B and the normal vector to the surface

As we see, the magnetic flux depends not only on B and A, but also on the orientation of the coil with respect to the magnetic field.

3. False

Explanation:

- Sound waves are mechanical waves: mechanical waves are waves consisting of oscillations of the particles in a medium. Due to their nature, therefore, mechanical waves can propagate only in the presence of a medium

- Electromagnetic waves are NOT mechanical waves: they consist of oscillations of electric and magnetic fields, in a direction perpendicular to the direction of propagation of the wave. Since em waves are not mechanical waves, they do NOT need a medium to propagate, since they can also travel through a vacuum; therefore the original statement is false.

5 0

3 years ago

What is the density of a rock with a mass of .235kg

Andre45 [30]

Answer:

where is volume? formula of density is: mass/volume so volume must be there

4 0

3 years ago

A stretched string is 1.91 m long and has a mass of 19.3 g . When the string is oscillated at 440 Hz , which is the frequency of

vovangra [49]

Answer:

so tension in the string is 57.199 N

Explanation:

given data

long = 1.91 m

mass = 19.3 g

oscillated = 440 Hz

wavelength = 17.1 cm = 0.171 m

to find out

tension in the string

solution

we know equation

v = √(T/u) ...............................1

here

v = oscillation × wavelength = 440 × 0.171 = 75.24 m/s

and u = mass / length = 0.0193 / 1.91 = 0.010104712

so from equation 1

v = √(T/u)

75.24 = √(T/0.010104)

T = 57.199 N

so tension in the string is 57.199 N

5 0

4 years ago

How do radio waves help support the big bang theory

lubasha [3.4K]

Answer:

The Big Bang theory predicts that the early universe was a very hot place and that as it expands, the gas within it cools. Thus the universe should be filled with radiation that is literally the remnant heat left over from the Big Bang, called the “cosmic microwave background", or CMB.

Explanation:

5 0

3 years ago