<h2>
Answer: an underground lake</h2>
Explanation:
In general, sound (mechanical waves) travels faster in solids than in liquids, and faster in liquids than in gases. This is because <u>the speed of the mechanical waves is determined by a relationship between the elastic properties of the medium </u>in which they are propagated and the mass per unit volume of the medium (that is:<u>density</u>).
In other words: The speed of sound varies depending on the medium through which the sound waves travel.
So, if we are told the sound wave initially had a speed of 4,000 m/s and it suddenly decreases to 1,500 m/s, this means the sound waves passed from a solid medium to a liquid medium.
Hence, the correct option is: an underground lake.
<span>Changes that occur during metamorphism ... The metamorphic rock shale normally becomes following low grade metamorphism.</span>
Answer:
Explanation: Magnets can be used in space. ... Magnets don't need gravity or air. Instead, their power comes from the electromagnetic field they generate all by themselves. One class of magnets, called electromagnets, does need electricity to work.
Answer:
635.36J
Explanation:
The formulae to apply in this question is;
q=m*c*ΔФ where q is the heat needed, m is mass,c is specific heat capacity and ΔФ is change in temperatures
Given that;
m=8 g
ΔФ= 19°C - 0°C= 19°C
c=4.18J/g.°C
Substitute values
q= 8×4.18×19 = 635.36J
Speed is a constant direction of where you go, constant motion, and velocity is the displacement of a objects direction, plus the direction the object is traveling to.
