Answer: d. Electromagnetic wave
Explanation:
Light is an electromagnetic wave, no matter is wavelength or color.
In this sense, the main characteristic of this type of wave is that it can propagate trhough vacumm, it is not necessary a medium. In addition, electromagnetic waves are transversal waves, this means the electric field oscillates in all normal directions to the direction of wave propagation.
The equation is garbled and the question is missing.
I found this equation for the same statement:
S = - 2.7t ^2 + 30t + 6.5
And one question is: after how many seconds is the ball 12 feet above the moon's surface?
Given that S is the height of the ball, you just have to replace S with 12 and solve for t.
=> 12 = - 2.7 t^2 + 30t + 6.5
=> 2.7t^2 - 30t - 6.5 + 12 = 0
=> 2.7t^2 - 30t + 5.5 = 0
Now you can use the quadratic equation fo find t:
t = { 30 +/- √ [30^2) - 4(2.7)(5.5)] } / (2*2.7)
=> t = 0.186s and t = 10.925 s
Answer: after 0.186 s the ball is at 12 feet over the surface, and again 10.925 s
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Answer:
Explanation:
Volume of block A = 10 x 6 x 1 = 60 cm³
Mass of block A = 630 g
density of mass A = mass / density
= 630 / 60 = 10.5g / cm³
Volume of block B = 5 x 5 x 3 = 75 cm³
Mass of block A = 604 g
density of mass A = mass / density
= 604 / 75 = 8.05 g / cm³
Since density of both A and B are less than that of mercury , both will float in mercury.
In a gear train with two gears, the gear ratio is defined as follows
where

is the angular velocity of the input gear while

is the angular velocity of the output gear.
This can be rewritten as a function of the number of teeth of the gears. In fact, the angular velocity of a gear is inversely proportional to the radius r of the gear:

But the radius is proportional to the number of teeth N of the gear. Therefore we can rewrite the gear ratio also as