Does anyone know this?

A train travels 8.81 m/s in a -51.0° direction.

Bad White [126]

The displacement of the train after 2.23 seconds is 25.4 m.

<h3>Resultant velocity of the train</h3>

The resultant velocity of the train is calculated as follows;

R² = vi² + vf² - 2vivf cos(θ)

where;

θ is the angle between the velocity = (90 - 51) + 37 = 76⁰

R² = 8.81² + 9.66² - 2(8.81 x 9.66) cos(76)

R² = 129.75

R = √129.75

R = 11.39 m/s

<h3>Displacement of the train</h3>

The displacement of the train is the change in position of the train after a given period of time.

The displacement is calculated as follows;

Δx = vt

Δx = 11.39 m/s x 2.23 s

Δx = 25.4 m

Thus, the displacement of the train after 2.23 seconds is 25.4 m.

Learn more about displacement here: brainly.com/question/2109763

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5 0

2 years ago

- A particular light source gives off light waves with a measured wavelength of

skad [1K]

Answer:

f = 1.5 x 10¹⁵ Hz

Explanation:

Light is an electromagnetic wave and we know that the speed of light is a constant which is

3 x 10⁸ m/s.

Knowing this; v = λ x f

λ = wavelength

f= frequency of light

v = seed of light

f = v/λ

f = 3 x 10⁸m/s / 2.0 x 10-⁷ m

f = 1.5 x 10¹⁵ Hz

8 0

2 years ago

Give a simple explanation why the pressure changes by this factor.Word Bank:1. two2.greater3.smaller4.four5.eightDoubling the sp

diamong [38]

Answer

speed of the molecules

s₁ = v t

when velocity is doubled

s₂ = (2 v)t

= 2 s₁

they will hit the wall of container two times as often.

the momentum of molecule

p₁ = mvr

p₂ = m(2v)r = 2(mvr)

= 2 p₁

the momentum change is two times as great.

force is change in momentum

Δp = F(Δt)

mv-(-mv) = 2 mv

$F = \dfrac{2 mv}{\Delta t}$

F α v

therefore average force impart to the wall on each collision is two times

$p = \dfrac{F_{total}}{A}$

$p = \dfrac{Nmv^2}{3LA}$

p α v²

here the velocity is doubled it means pressure becomes four times.

6 0

3 years ago

Tennis balls traveling at greater than 100 mph routinely bounce off tennis rackets. At some sufficiently high speed, however, th

Kipish [7]

Answer:

Probability of tunneling is $10^{- 1.17\times 10^{32}}$

Solution:

As per the question:

Velocity of the tennis ball, v = 120 mph = 54 m/s

Mass of the tennis ball, m = 100 g = 0.1 kg

Thickness of the tennis ball, t = 2.0 mm = $2.0\times 10^{- 3}\ m$

Max velocity of the tennis ball, $v_{m} = 200\ mph$ = 89 m/s

Now,

The maximum kinetic energy of the tennis ball is given by:

$KE = \frac{1}{2}mv_{m}^{2} = \frac{1}{2}\times 0.1\times 89^{2} = 396.05\ J$

Kinetic energy of the tennis ball, KE' = $\frac{1}{2}mv^{2} = 0.5\times 0.1\times 54^{2} = 154.8\ m/s$

Now, the distance the ball can penetrate to is given by:

$\eta = \frac{\bar{h}}{\sqrt{2m(KE - KE')}}$

$\bar{h} = \frac{h}{2\pi} = \frac{6.626\times 10^{- 34}}{2\pi} = 1.0545\times 10^{- 34}\ Js$

Thus

$\eta = \frac{1.0545\times 10^{- 34}}{\sqrt{2\times 0.1(396.05 - 154.8)}}$

$\eta = 1.52\times 10^{-35}\ m$

Now,

We can calculate the tunneling probability as:

$P(t) = e^{\frac{- 2t}{\eta}}$

$P(t) = e^{\frac{- 2\times 2.0\times 10^{- 3}}{1.52\times 10^{-35}}} = e^{-2.63\times 10^{32}}$

$P(t) = e^{-2.63\times 10^{32}}$

Taking log on both the sides:

$logP(t) = -2.63\times 10^{32} loge$

$P(t) = 10^{- 1.17\times 10^{32}}$

6 0

3 years ago

Assume that a uniform magnetic field is directed into thispage. If an electron is released with an initial velocity directedfrom

Feliz [49]

Answer:

B). to the right

Explanation:

Since the direction of magnetic field is into the page

So here we know that

$B = B_o(-\hat k)$

now the velocity is from bottom to top

so we have

$v = v_o \hat j$

now the force on the moving charge is given as

$\vec F = q(\vec v \times \vec B)$

now we have

$\vec F = (-e)(v_o \hat j \times B_o(-\hat k))$

$\vec F = e v_o B \hat i$

so force will be towards Right

7 0

3 years ago