Question 3 (5 points)

Which of these are not mechanical waves and can be used to send a signal to astronauts on the moon?

Gekata [30.6K]

Radiowaves are electromagnetic waves and don't need a medium to travel through so B

5 0

4 years ago

3. Tyrone wants to determine how fast a bowling ball travels when it is bowled. He uses a stopwatch to

SVEN [57.7K]

Meters would be the best way to record the length

7 0

3 years ago

A point charge Q is held at a distance r from the center of a dipole that consists of two charges ±qseparated by a distance s. T

atroni [7]

Answer:

The magnitude of the force on the dipole due to the charge Q = $\rm \dfrac{1}{\epsilon_o}\times \dfrac{1}{4\pi }\dfrac{2qQs}{r^3}.$

The magnitude of the torque on the dipole = $\rm \dfrac{1}{\epsilon_o}\times \dfrac{1}{4\pi}\dfrac{2qQs^2}{r^3}.$

Explanation:

Given that a point charge Q is held at a distance r from the center of a dipole that consists of two charges ±q, separated by a distance s and the charge Q is located in the plane that bisects the dipole.

The magnitude of the electric field that the dipole exerts at the position where the charge Q is held is given by

$\rm E = \dfrac{k2qs}{(r^2+s^2)^{3/2}}.$

where,

k is the Coulomb's constant, having value = $\dfrac{1}{4\pi \epsilon_o}$

$\epsilon_o$ is the electrical permittivity of free space.

Also, r>>s, therefore, $\rm r^2+s^2\approx r^2.$

$\rm E = \dfrac{k2qs}{(r^2)^{3/2}}=\dfrac{k2qs}{r^3}.$

The magnitude of the electric force F on a charge q placed at a point and the magnitude of the electric field E at that point are related as

$\rm F=qE$

Therefore, the electric force on the charge Q due to the dipole is given by

$\rm F=Q\dfrac{k2qs}{r^3}=\dfrac{1}{4\pi \epsilon_o}\dfrac{2qQs}{r^3}.$

According to Newton's third law of motion, the magnitude of the force exerted by the dipole on the charge Q is same as the magnitude of the force exerted by the charge on the dipole.

Thus, the magnitude of the force on the dipole due to the charge Q = $\dfrac{1}{\epsilon_o}\times \dfrac{1}{4\pi }\dfrac{2qQs}{r^3}.$

The magnitude of the torque on the dipole is given by

$\rm \tau = Fs\ \sin\theta$

Since the charge Q is placed in the plane that bisects the dipole, therefore, $\theta = 90^\circ$ .

$\rm \tau = \dfrac{1}{4\pi \epsilon_o}\dfrac{2qQs}{r^3}\cdot s\cdot 1=\dfrac{1}{4\pi \epsilon_o}\dfrac{2qQs^2}{r^3}.$

4 0

3 years ago

Start Point: an unlit match. End Point: a lit match.

nalin [4]

Answer:

Ok

Explanation:

5 0

3 years ago

a spacecraft that seems to be motionless in deep space is given some type of quick push. which statement describes what will hap

bogdanovich [222]

An applied force applied causes a body such as the spacecraft to move. The magnitude of the force determines the change in the velocity

What will happen to the spacecraft is given by option C. from among the possible question options.

C. The spacecraft will begin to move and it will continue moving until it is stopped by an equal and opposite force

Reason:

The possible question options obtained from a similar question includes;

A. The spacecraft will move for some time then stop slowly

B. Air resistance will prevent the spacecraft from moving

C. The spacecraft will begin to move and the motion will continue until a force equal and opposite to the applied force stops it

D. The quick push will not cause the spacecraft to move, as a quick push works on Earth only

The state of the space craft = Motionless

Location of the spacecraft = Deep space

Type of force applied = Quick push

The statement that describes what will happen = Required

Solution;

Let F, represent the force applied, and let Δt be the duration of the applied force, we have;

The impulse of the force, F × Δt = m·(v₂ - v₁)

Where;

m = The mass of the spacecraft

v₁ = The initial velocity of the spacecraft = 0

v₂ = Final velocity of the spacecraft

Plugging in v₁ = 0, gives;

F × Δt = m·v₂

The space craft is given a velocity, v₂, and according to Newton's First Law of Motion, it continues moving in a straight line until another force acts on it

Therefore, the correct option is option C. The spacecraft will begin to move and the motion will continue until it is stopped by an equal and opposite force

Learn more about Newton's First Law of Motion here:

brainly.com/question/20841616

8 0

3 years ago