Determine the momentum of a helium atom (m = 6.696 x 10-27 kg) if the atom is traveling at 1.03% of the speed of light.

Two tiny, spherical water drops, with identical charges of −8.00 ✕ 10^(−17) C, have a center-to-center separation of 2.00 cm.

Damm [24]

Answer:

F=1.4384×10⁻¹⁹N

Explanation:

Given Data

Charge q= -8.00×10⁻¹⁷C

Distance r=2.00 cm=0.02 m

To find

Electrostatic force

Solution

The electrostatic force between between them can be calculated from Coulombs law as

$F=\frac{kq^{2} }{r^{2} }$

Substitute the given values we get

$F=\frac{(8.99*10^{9} )*(-8.00*10^{-17} )^{2} }{(0.02)^{2} }\\ F=1.4384*10^{-19} N$

7 0

3 years ago

A bird flies 3.6 km due west and then 1.8 km due north. Another bird flies 1.8 km due west and 3.6 km due north. What is the ang

kondor19780726 [428]

Define unit vectors as follows:
$\hat{i}$ is in the eastern direction.
$\hat{j}$ is in the northern direction.

The position of the first bird is
$\vec{a} = -3.6 \, \hat{i} + 1.8 \, \hat{j}$

The position of the second bird is
$\vec{b} = - 1.8 \, \hat{i} + 3.6 \, \hat{j}$

Let θ = the angle between the net displacement vector for the two birds.
By definition,
$\vec{a} . \vec{b} = |a| |b| cos\theta \\\\ \theta = cos^{-1} ( \frac{\vec{a}.\vec{b}}{|a||b|} )$

$\vec{a}.\vec{b} = (-3.6)(-1.8)+(3.6)(1.8) = 12.96$
$|a| = \sqrt{3.24+12.96} =4.025$
Similarly,
|b| = 4.025

Therefore
$\theta = cos^{-1} \frac{12.96}{4.025^{2}} =36.9^{o}$

Answer: 36.9°

5 0

3 years ago

What will change the velocity of a periodic wave?

Georgia [21]

If it's a mechanical wave, then its speed depends on the physical characteristics of the medium.

If it's an electromagnetic wave, then its speed depends on the
electrical characteristics of the medium.

Either way, the properties of the medium determine the wave speed.
You want to change the speed ? You have to change the properties
of the medium.

7 0

3 years ago

What happens when a force exerted on an object cause the object to move?

Charra [1.4K]

Answer:

B. Kinetic energy is created

Explanation:

5 0

3 years ago

Read 2 more answers

Match the indices of refraction with the corresponding effects on the waves.

Yanka [14]

Answer:

B) waves speed up

C) waves bend away from the normal

Explanation:

The index of refraction of a material is the ratio between the speed of light in a vacuum and the speed of light in that medium:

$n=\frac{c}{v}$

where

c is the speed of light in a vacuum

v is the speed of light in the medium

We can re-arrange this equation as:

$v=\frac{c}{n}$

So from this we already see that if the index of refraction is lower, the speed of light in the medium will be higher, so one correct option is

B) waves speed up

Moreover, when light enters a medium bends according to Snell's Law:

$n_1 sin \theta_1 = n_2 sin \theta_2$

where

$n_1 ,n_2$ are the index of refraction of the 1st and 2nd medium

$\theta_1,\theta_2$ are the angles made by the incident ray and refracted ray with the normal to the interface

We can rewrite the equation as

$sin \theta_2 = \frac{n_1}{n_2}sin \theta_1$

So we see that if the index of refraction of the second medium is lower ( $n_2$ ), then the ratio $\frac{n_1}{n_2}$ is larger than 1, so the angle of refraction is larger than the angle of incidence:

$\theta_2>\theta_1$

This means that the wave will bend away from the normal. So the other correct option is

C) waves bend away from the normal

3 0

4 years ago