Answer:
391.67Hz
Explanation:
The fundamental frequency formula in string is expressed as;
Fo = V/2L
V is the velocity of the wave = 329m/s
L is the length of the string = 42cm = 0.42m
Substitute
Fo = 329/2(0.42)
Fo = 329/0.84
Fo = 391.67Hertz
Hence the fundamental frequency of a mandolin string is 391.67Hz
Illluminance is the measurement of photometric power. That means, illuminance is the rate of photometric flux that is received by a surface per area. It is usually expressed as a unit of W/m^2.
Thus, from the choices, the answer we're looking for is illuminance<span>.</span>
The form of energy that can move from place to place across the universe is light energy. On earth, the main source of this energy is Sun. Most of the light energy comes from the sun because it is the primary source of all the energies. The food, fossil fuels, movement of winds, etc all exists due to Sun. Without sun, there won't be any light energy on the earth. In all the processes which occur on earth has a direct or indirect involvement of light energy which comes from sun.
Gamma rays are the highest energy EM radiation and typically have energies greater than 100 keV, frequencies greater than 1019 Hz, and wavelengths less than 10 picometers.
Answer:
1. 
2. 
Explanation:
1. According to Newton's law of motion, the puck motion is affected by the acceleration, which is generated by the push force F.
In Newton's 2nd law: F = ma
where m is the mass of the object and a is the resulted acceleration. So in the 2nd experiment, if we double the mass, a would be reduced by half.

Since the puck start from rest, in the 1st experiment, to achieve speed of v it would take t time

Now that acceleration is halved:


You would need to push for twice amount of time 
2. The distance traveled by the puck is as the following equation:

So if the acceleration is halved while maintaining the same d:

As
, then
. Also 



So t increased by 1.14