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3 years ago

13

A boy drops a coin down a well that is 225 m deep. How long does it take the coin to hit the bottom of the well? (Please state y

our final answer)

1 answer:

Alexxandr [17]3 years ago

7 0

I had the same question. I'm pretty sure it's 23 seconds. :)

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The average speed of a nitrogen molecule in air is about 6.70×102 m/s, and its mass is 4.68×10-26 kg.

Otrada [13]

Answer:

a) a = 3.06 10¹⁵ m / s , b) F= 1.43 10⁻¹⁰ N, c) F_total = 14.32 10⁻²⁶ N

Explanation:

This exercise will average solve using the moment relationship.

a ) let's use the relationship between momentum and momentum

I = ∫ F dt = Δp

F t = m $v_{f}$ - m v₀

F = m (v_{f} -v₀o) / t

in the exercise indicates that the speed module is the same, but in the opposite direction

F = m (-2v) / t

if we use Newton's second law

F = m a

we substitute

- 2 mv / t = m a

a = - 2 v / t

let's calculate

a = - 2 4.59 10²/3 10⁻¹³

a = 3.06 10¹⁵ m / s

b) F= m a

F= 4.68 10⁻²⁶ 3.06 10¹⁵

F= 1.43 10⁻¹⁰ N

c) if we hit the wall for 1015 each exerts a force F

F_total = n F

F_total = n m a

F_total = 10¹⁵ 4.68 10⁻²⁶ 3.06 10¹⁵

F_total = 14.32 10⁻²⁶ N

8 0

3 years ago

Which law of physics relates electric fields and current

riadik2000 [5.3K]

Answer:

Ohms law

Explanation:

Which states that the current flowing through any cross-section of the conductor is directly proportional to the potential differenceapplied across its end, provided physical conditions like temperature and pressure remain constant.

7 0

3 years ago

What part of the electromagnetic spectrum can be seen by humans

Amanda [17]

Answer:

Visible light

Explanation:

Electromagnetic spectrum is the classification of the electromagnetic waves according to their frequency/wavelength. In order from the shortest to the longest wavelength, we have

Gamma rays

X-rays

Ultraviolet

Visible light

Infrared

Microwaves

Radio waves

All these waves are invisible to human eye, except for the part referred as 'visible light'. The electromagnetic waves of this part of the spectrum are visible to human eye, and they appear as a different color depending on their wavelength. In particular, we have:

Violet: 380-450 nm

Blue: 450-495 nm

Green: 495-570 nm

Yellow: 570-590 nm

Orange: 590-620 nm

Red: 620-750 nm

4 0

3 years ago

A stretched string has a mass per unit length of 5.40 g/cm and a tension of 17.5 N. A sinusoidal wave on this string has an ampl

kondaur [170]

Answer:

Part a)

$y_m = 0.157 mm$

part b)

$k = 101.8 rad/m$

Part c)

$\omega = 579.3 rad/s$

Part d)

here since wave is moving in negative direction so the sign of $\omega$ must be positive

Explanation:

As we know that the speed of wave in string is given by

$v = \sqrt{\frac{T}{m/L}}$

so we have

$T = 17.5 N$

$m/L = 5.4 g/cm = 0.54 kg/m$

now we have

$v = \sqrt{\frac{17.5}{0.54}}$

$v = 5.69 m/s$

now we have

Part a)

$y_m$ = amplitude of wave

$y_m = 0.157 mm$

part b)

$k = \frac{\omega}{v}$

here we know that

$\omega = 2\pi f$

$\omega = 2\pi(92.2) = 579.3 rad/s$

so we have

$k = \frac{579.3}{5.69}$

$k = 101.8 rad/m$

Part c)

$\omega = 579.3 rad/s$

Part d)

here since wave is moving in negative direction so the sign of $\omega$ must be positive

4 0

3 years ago

Structures on a bird feather act like a diffraction grating having 8000 8000 lines per centimeter. What is the angle of the firs

sammy [17]

Answer:

Angle of first order maximum, $\theta=21.19^{\circ}$

Explanation:

Given that,

Wavelength of the light, $\lambda=452\ nm=452\times 10^{-9}\ m$

Number of lines, N = 8000 per cm

The relation between the number of lines and the slit width is given by :

$d=\dfrac{1}{N}$

$d=\dfrac{1}{8000/cm}$

$d=0.000125\ cm=1.25\times 10^{-6}\ m$

The equation of grating is given by :

$d\ sin\theta=n\lambda$

n = 1

$sin\theta=\dfrac{\lambda}{d}$

$sin\theta=\dfrac{452\times 10^{-9}}{1.25\times 10^{-6}}$

$\theta=21.19^{\circ}$

So, the angle of the first-order maximum is 21.19 degrees. Hence, this is the required solution.

6 0

3 years ago