Answer: 996m/s
Explanation:
Formula for calculating velocity of wave in a stretched string is
V = √T/M where;
V is the velocity of wave
T is tension
M is the mass per unit length of the wire(m/L)
Since the second wire is twice as far apart as the first, it will be L2 = 2L1
Let V1 and V2 be the speed of the shorter and longer wire respectively
V1 = √T/M1... 1
V2 = √T/M2... 2
Since V1 = 249m/s, M1 = m/L1 M2 = m/L2 = m/2L1
The equations will now become
249 = √T/(m/L1) ... 3
V2 = √T/(m/2L1)... 4
From 3,
249² = TL1/m...5
From 4,
V2²= 2TL1/m... 6
Dividing equation 5 by 6 we have;
249²/V2² = TL1/m×m/2TL1
{249/V2}² = 1/2
249/V2 = (1/2)²
249/V2 = 1/4
V2 = 249×4
V2 = 996m/s
Therefore the speed of the wave on the longer wire is 996m/s
Answer:
The direction is due south
Explanation:
From the question we are told that
The energy of the electron is 
The earths magnetic field is 
Generally the force on the electron is perpendicular to the velocity of the elecrton and the magnetic field and this is mathematically reresented as

On the first uploaded image is an illustration of the movement of the electron
Looking at the diagram we can see that in terms of direction the magnetic force is


generally i cross k = -j
so the equation above becomes


This show that the direction is towards the south
This topic is actually quite controversial, but the answer in this case would be C.
Just some food for thought, the 2nd law of thermodynamics entropy of the universe is always increasing, but that doesn't necessarily mean that earth's entropy has to. As long as the net change in entropy of the universe is increasing it doesn't matter if one planet is decreasing a nominal amount. Next, Earth as said is not a closed system and you could argue that the sunlight and energy from the sun is increasing the total energy within the system that is earth meaning that it is increasing in entropy. Next, if you consider increasing entropy as an increase in the number of possible permutations that the universe or parts of the universe can take, then it is completely possible that an ordered planet and life is possible, although rare. This theory explains why there are so many life forms and why entropy is actually increasing when divergent evolution occurs.
Answer:
The percentage error e% = Δm/m 100
Explanation:
The absolute error is the assessment with which measurements are made, it is given by the minimum reading value of a given instrument.
The accepted value is the value measured in an instrument. Or the one calculated by an experiment.
The percentage error is the ratio of the absolute error between the value of the average per 100
e% = Δm/m 100