Answer:
The mass of the block is 1250g.
Explanation:
Given that the formula for density is ρ = mass/volume. Then you have to substitute the values into the formula :
Let density = 250,
Let volume = 5,
Sound waves are known to be the one that's not considered as a type of electromagnetic energy. As for microwaves and x-rays, they tend to share the same frequencies that can be considered as electromagnetic, and sound waves have a different frequency than them.
Answer:
<em>D. refraction</em>
Explanation:
Refraction: Refraction is change in direction of light rays. Refraction occurs whenever light rays travels from a transparent medium to another transparent medium of different density. The abrupt change in direction at the surface of the surface of the two media is referred to as <em>refraction</em><em>.</em>
<em>Refraction occurs when light travels from air to glass or from air to liquid.</em>
<em>Laws Of Refraction:</em>
(i) The incident ray, the refracted ray and the normal, all at the point of incident lies in the same plane.
(ii) The ratio of the sine of the angle of incident to the sine of the angle of refraction is a constant for a given pair of media.
<em>Thus the right option is D. refraction</em>
Explanation:
formula for force is:
force=mass × acceleration
but in case of friction
force =coefficient of friction × Normal Reaction
F. = u × R
U = F/R
but when placed horizontally
R= M×G
M=mass=60kg
G=Gravity(10m/s or 9.8m/s)
F=140N
U=140/60×10
U=140/600
U=0.2333333333
approximately to 3 significant figures
U=0.233
if i am correct rate it 5 star
Answer:
Explanation:
In all atoms, the number of protons = number of electrons, as a result the atom is neutral. Losing or gaining electrons will make the atom electrically charged and we call an electrically charged atom an ion.
Ca 2+ would be the symbol because losing two negative electrons makes calcium's nucleus more positive by two protons.
