Sound can travel through a medium, but it does not require a medium.<br> a. True.<br> b. False

At what distance from the centre of the earth its acceleration due to gravity becomes one third only? [Mass and radius of earth

Kipish [7]

Answer:

235

Explanation:

3 0

3 years ago

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Which characteristic best identifies a pure substance?

RSB [31]

<span> A pure substance is an material which contains atoms of only one kind.
It has fixed physical and chemical properties such as boiling point, melting point, valency, density and more.</span>

8 0

3 years ago

A _______ is a repeating disturbance or vibration that transfers or moves energy from place to place without transporting mass.

Harman [31]

Answer: wave

Explanation:

These are the basic definitions and characteristic of the terms given, which show tha the only rigth answer is the second option: wave.

1) Force is an interaction. There are four natural forces: electrostatic, gravity, strong nuclear force and weak nuclear force.

2) Wave: is a sequence of pulses or vibrations that cause the continuous transportation of energy (propagation). There is not transport of mass, only energy.

Some examples of waves are sound waves, electromagnetic waves (light, radio waves, micro waves, infrarred waves, ultraviolet waves).

3) Vacuum: is the absence of matter; empty space. Only electromagnetic waves can travel through vacuum; other waves need a medium to travel.

4) Medium: any matter is a medium: a solid, the air, a liquid, all of them are media through which waves can transport its energy, depending of the wavelength.

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3 years ago

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Pluto’s diameter is approximately 2370 km, and the diameter of its satellite Charon is 1250 km. Although the distance varies, th

MissTica

Answer:

$r_{cm} = 2520.5 km$