The first thing you should know for this case is that density is defined as the quotient between mass and volume:
D = M / V
In addition, you should keep in mind the following conversion:
1Kg = 1000g
Substituting the values we have:
D = (23.0 * 1000) / (2920) = 7.88 g / cm ^ 3
answer
the density of the iron plate is 7.88 g / cm ^ 3
Answer:
option B
Explanation:
given,
height of building = 0.1 km
ball strikes horizontally to ground at = 65 m
speed at which the ball strike = ?
vertical velocity = 0 m/s
time at which the ball strike
t = 4.53 s
vertical velocity at the time 4.53 s = g × t = 9.8 × 4.53 = 44.39 m/s
horizontal velocity = 
=14.35 m/s
speed of the ball = 
= 46.65 m/s
hence, the speed of the ball just before it strike the ground = 47 m/s
The correct answer is option B
Sound waves.
Eathquake P-Waves
Answer:
Because it radiates a spectre of frequencies, this means that it radiates in a continuous range of frequencies, ones with more intensity (like x-ray and ultraviolet) and others with less intensity (like the visible light). While most of the radiation is not in the visible range, there still is a part of the radiation in the visible spectre. And while this part is not the most intense part, the radiation is so large that we can see a very bright visible light.
