Answer:
iv) It is 9x bigger than before
Explanation:
As the amplitudes of the new speakers add directly with the original one, taking into account the phase that they have, the composed amplitude of the sound wave is as follows:
At = A + 4A -2A = 3 A
The intensity of the wave, assuming it propagates evenly in all directions, is constant at a given distance from the source, and can be expressed as follows:
I = P/A
where P= Power of the wave source, A= Area (for a point source, is equal to the surface area of a sphere of radius r, where is r is the distance to the source along a straight line)
For a sinusoidal wave, the power is proportional to the square of the amplitude, so the intensity is proportional to the square of the amplitude also.
If the amplitude changes increasing three times, the change in intensity will be proportional to the square of the change in amplitude, i.e., it will be 9 times bigger.
So, the statement iv) is the right one.
The answer for this question is Control Variable because it doesn’t change throughout the experiment.
Weight is equivalent to the product of the mass of an object and the strength of the gravitational field.
Using:
F = ma
a = 8.2 / 5
a = 1.64 N/kg
The gravitational field strength is equivalent to 1.64 N/kg.
Answer:
16.1 m/s
Explanation:
We can solve the problem by using the law of conservation of energy.
At the beginning, the spring is compressed by x = 35 cm = 0.35 m, and it stores an elastic potential energy given by

where k = 316 N/m is the spring constant. Once the block is released, the spring returns to its natural length and all its elastic potential energy is converted into kinetic energy of the block (which starts moving). This kinetic energy is equal to

where m = 0.15 kg is the mass of the block and v is its speed.
Since the energy must be conserved, we can equate the initial elastic energy of the spring to the final kinetic energy of the block, and from the equation we obtain we can find the speed of the block:
