What is heroism???<br><br><br>plz answer

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

A truck moves 60 km West, and then 80 km North, and then

stira [4]

$▪▪▪▪▪▪▪▪▪▪▪▪▪ {\huge\mathfrak{Answer}}▪▪▪▪▪▪▪▪▪▪▪▪▪▪$

Distance travelled by the truck is ~

$\boxed{240 \: \: km}$

And it's displacement is ~

$\boxed{0 \: \: km}$

$\large \boxed{ \mathfrak{Step\:\: By\:\:Step\:\:Explanation}}$

See the diagram in attachment for reference ~

Let O be the initial point, It travels 60 km towards west till point B and then 80 km towards north till point P and returns to initial point O in a straight line, now as we can observe here, it forms a right angled Triangle.

The measure of two legs is 60 km and 80 km, let's find the hypotenuse ~

According to Pythagoras theorem ~

hypotenuse² = sum of squares of other two legs

that is ~

$h {}^{2} = 60 {}^{2} + 80 {}^{2}$

${h}^{2} = 3600 + 640 0$

$h {}^{2} = 10000$

$h = \sqrt{10000}$

$h = \sqrt{100 \times 100}{}$

$h = 100 \: \: km$

So, the distance between the point A and O is 100 km

Now, The total distance is equal to the distance covered through actual path that is ~

60 km + 80 km + 100 km

240 km

And displacement is the distance between the final point and initial point, but since the truck returns to the point from where it started the journey, so the final and initial point is same therefore displacement is equal to 0.

4 0

3 years ago

. What happens to the polarity of an electromagnet when the direction of the current passing through it is reversed?

eduard

Answer:

The polarity of electromagnet also gets reversed when the direction of current is reversed. The current flows from negative terminal to positive terminal in an electromagnet due to the flow of electrons so polarity is also established in the electromagnet. As, the current direction is reversed, the polarity of magnet also gets reversed because the polarity of magnet depends on the direction of the current.

6 0

4 years ago

What is specific heat capacity?

leonid [27]

B is the ans for this question

4 0

3 years ago

A car with mass mc = 1490 kg is traveling west through an intersection at a magnitude of velocity of vc = 9.5 m/s when a truck o

icang [17]

Answer:

v= - 4.507 i - 2.363 j

Explanation:

Given that

mc= 1490 kg

vc= 9.5 m/s ( - i)

mt= 1650 kg

vt = 6.4 m/s ( -j)

There is any external force so linear momentum will remain conserve.

Lets take final speed is v.

mc .vc + mt . vt = ( mc+mt) v

1490 x 9.5 ( - i) + 1650 x 6.4 ( -j) = ( 1490+1650) v

14,155 ( -i) + 10,560 ( - j) = 3140 v

v= - 4.507 i - 2.363 j

3 0

4 years ago

What is heroism???plz answer​

What is heroism???plz answer