Please help me with question 1 of this reflections and refraction of waves worksheet, I’m really confused as to this labelling!

In what ways does a river carry its load?

MArishka [77]

It carry its loads from the sand and outher partials in it

7 0

3 years ago

Write the equation for speed

zzz [600]

Answer:

Distance / Time = Speed

Explanation:

This is because you want to see how much distance you cover within a time interval.

For example, MPH, is a unit for speed, which is miles (distance) per hour (time)

7 0

4 years ago

The Bohr model of the hydrogen atom pictures the electron as a tiny particle moving in a circular orbit about a stationary proto

igor_vitrenko [27]

a) The angular velocity of the electron is $4.12\cdot 10^{16} rad/s$

b) The number of revolutions per second is $6.54\cdot 10^{15}$ rev/s

c) The centripetal acceleration of the electron is $8.98\cdot 10^{22} m/s^2$

Explanation:

a)

This is a problem of uniform circular motion: in fact, the electron orbits around the proton in a uniform circular motion.

The angular velocity of an object in uniform circular motion is given by

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

where

v is the linear speed

r is the radius of the trajectory

For the electron orbiting around the proton, we have

$v=2.18 \cdot 10^6 m/s$

$r=5.29\cdot 10^{-11} m$

Therefore, the angular velocity is

$\omega=\frac{2.18\cdot 10^6}{5.29\cdot 10^{-11}}=4.12\cdot 10^{16} rad/s$

b)

The period of revolution of the electron is given by

$T=\frac{2\pi}{\omega}$

where

$\omega = 4.12\cdot 10^{16}rad/s$ is the angular velocity

Substituting,

$T=\frac{2\pi}{4.12\cdot 10^{16}}=1.53\cdot 10^{-16}s$

The period is the time the electron takes to make one complete orbit around the proton; therefore, the number of revolutions of the electrons in one second is:

$f=\frac{1}{T}=\frac{1}{1.53\cdot 10^{-16}}=6.54\cdot 10^{15}$ rev/s

c)

The centripetal acceleration of an object in circular motion is

$a=\frac{v^2}{r}$

where

v is the linear speed

r is the radius of the circle

For the electron, we have

$v=2.18 \cdot 10^6 m/s$

$r=5.29\cdot 10^{-11} m$

Therefore, the centripetal acceleration is

$a=\frac{(2.18\cdot 10^6)^2}{5.29\cdot 10^{-11}}=8.98\cdot 10^{22} m/s^2$

Learn more about circular motion:

brainly.com/question/2562955

brainly.com/question/6372960

#LearnwithBrainly

7 0

4 years ago

Which statement about the minerals plagioclase feldspar, gypsum, biotite mica, and talc can best be inferred from the chart? (1)

madreJ [45]

Answer:

(4) The physical and chemical properties of these minerals determine how humans use them.

Explanation:

All the materials and the metals found on earth shows certain characteristics naturally or in their physical state. These physical characteristics can be their look, their structure, their color, strength, melting point, boiling point, density, etc.

And chemical properties of the metals are defined as those characteristics or features of the metals that it exhibits when these metals reacts chemically.

The physical properties as well as the chemical properties distinguishes each metal from each other. These properties determines how people use these metals in their life.

7 0

3 years ago

At which temperature does the motion of atoms and molecules stop?

Scorpion4ik [409]

Answer:

0 Kelvin

Explanation:

Atoms in absolute temperature get approximatelly motionless since 0 Kelvin is -273 degrees Celcius. The kinetic energy of atoms/particles in matter has the possible lowest value ( almost zero), so that there is nothing colder than 0 Kelvin.

4 0

3 years ago