Answer:
2.1406 ×
m/sec
Explanation:
we know that energy is always conserved
so from the law of energy conservation

here V is the potential difference
we know that mass of proton = 1.67×
kg
we have given speed =50000m/sec
so potential difference 
now mass of electron =9.11×
so for electron

so the velocity of electron will be 2.1406×
m/sec
-- Equations #2 and #6 are both the same equation,
and are both correct.
-- If you divide each side by 'wavelength', you get Equation #4,
which is also correct.
-- If you divide each side by 'frequency', you get Equation #3,
which is also correct.
With some work, you can rearrange this one and use it to calculate
frequency.
Summary:
-- Equations #2, #3, #4, and #6 are all correct statements,
and can be used to find frequency.
-- Equations #1 and #5 are incorrect statements.
Answer:
16 km
Explanation:
Drawing a right triangle to model the problem helps. I started by drawing the lines of the triangle to model the hiker's journey- a vertical straight line for 11 km north and then a horizontal line connected to the top of it for 11 km east; I then drew the hypothenuse to connect the two lines.
The hypothenuse is what we have to solve for, so we will use the Pythagorean Theorem, a^2 + b^2 = c^2. Since both distances are 11 km both a and b in the equation are 11.
11^2 + 11^2 = c^2
121 + 121 = c^2
242 = c^2
c = 15.56
Rounding the answer makes it 16 km for the hiker's magnitude of displacement.
If the girl is also near the source of the sound, two alike sets of sounds will be heard.
Velocity = 14 m/s
Time = 20 s
Displacement = Velocity×Time = (14×20) m = 280 m
The displacement is 280 m towards the direction of motion.