The initial elastic potential energy stored in the spring is:
Then, the spring is released, all this potential energy is converted into kinetic energy of the eraser:
Then, the force of friction does a work to stop the eraser in this motion, and this work is equal to
where F is the magnitude of the friction force and d is the distance covered by the eraser.
For energy conservation, the work done by the friction force must be equal to the initial energy of the eraser, so:
and so we find d:
the answer you are looking for is the independent variable.
Answer:
1. 
: Synthesis
: Decomposition
: Combustion
4. 
: Double displacement
Explanation:
1. Synthesis reaction is a chemical reaction in which two reactants are combining to form one product.
Example: 
2. Decomposition is a type of chemical reaction in which one reactant gives two or more than two products.
Example: 
3. Combustion is a type of chemical reaction in which hydrocarbon is reacted with oxygen to form carbon dioxide and water.
Example:
4. Double displacement reaction is one in which exchange of ions take place.
Example: 
I'll just find out the path difference between the waves at the starting point. At infinity, the path difference will be zero because the observer will be infinitely far away from both. As the observer goes farther, the path difference keeps reducing till it reaches zero as the observer reaches infinity.
<span>Path difference at starting point = Distance from lower speaker - Distance from upper speaker = √((3)² + (2.5)²) - 2.5 = 1.405 m </span>
<span>Now to find wavelength. </span>
<span>Speed of sound in air at 20 degrees C = 343 m/s </span>
<span>Wavelength = 343 / 686 = 0.5 m </span>
<span>Destructive interference occurs when path difference = (2n + 1)λ/2 where n is an integer. </span>
<span>Maximum n possible can be found by, </span>
<span>(2n + 1)λ/2 < 1.405 </span>
<span>(2n + 1) < (1.4)(2) / (0.5) </span>
<span>2n < 5.6 - 1 </span>
<span>2n < 4.6 </span>
<span>n < 2.3 </span>
<span>So, we have 3 values of n, 0, 1 and 2. </span>
<span>Path differences are, λ/2, 3λ/2 and 5λ/2 which have values 0.25 m , 0.75 m and 1.25 m </span>
<span>But the question asks for distance from starting point. (sheesh!!) </span>
<span>Lets say the observer walked x distance. </span>
<span>Path difference = √((3)² + (2.5 + x)²) - (2.5 + x) </span>
<span>Equate this expression to the values obtained above to get the different values of x. </span>
Answer:
m = F/a = 50 / 1.2 = 41.6666.... 42 kg
Explanation:
