Answer:
0.786 Hz, 1.572 Hz, 2.358 Hz, 3.144 Hz
Explanation:
The fundamental frequency of a standing wave on a string is given by
where
L is the length of the string
T is the tension in the string
is the mass per unit length
For the string in the problem,
L = 30.0 m
T = 20.0 N
Substituting into the equation, we find the fundamental frequency:
The next frequencies (harmonics) are given by
with n being an integer number and f being the fundamental frequency.
So we get:
Actually, they're not. There's a group of stars and constellations arranged
around the pole of the sky that's visible at any time of any dark, clear night,
all year around. And any star or constellation in the rest of the sky is visible
for roughly 11 out of every 12 months ... at SOME time of the night.
Constellations appear to change drastically from one season to the next,
and even from one month to the next, only if you do your stargazing around
the same time every night.
Why does the night sky change at various times of the year ? Here's how to
think about it:
The Earth spins once a day. You spin along with the Earth, and your clock is
built to follow the sun . "Noon" is the time when the sun is directly over your
head, and "Midnight" is the time when the sun is directly beneath your feet.
Let's say that you go out and look at the stars tonight at midnight, when you're
facing directly away from the sun.
In 6 months from now, when you and the Earth are halfway around on the other
side of the sun, where are those same stars ? Now they're straight in the
direction of the sun. So they're directly overhead at Noon, not at Midnight.
THAT's why stars and constellations appear to be in a different part of the sky,
at the same time of night on different dates.
Answer: The first electromagnet has a more powerful current than
the second
Explanation:
Since the two electromagnets contain the same types of magnets and wires. If the magnet In the first moves much faster than the second. Therefore:
The first electromagnet has a more powerful current than the second
Because the induced EMF is proportional to the induced current.
Where the induced EMF depends on the speed of the magnet according to the formula below
EMF = BVL
So, increase in speed of the magnet will cause more powerful induced current and emf
Answer:
magnitude of force on charge 2Q = 
Direction of force on charge = 61 ⁰
Explanation:
The magnitude on the force on the charge can be evaluated by finding the net force acting on the charge 2Q i.e x-component of the net force and the y-component of the net force
║F║ = 
= after considering the forces coming from Q, 3Q and 4Q AND APPLYING COULOMBS LAW
magnitude of force acting on 2Q =
The direction of the force on charge 2Q is calculated as
tan ∅ = 
= 1.8284
therefore ∅ = 
1.8284
= 61⁰
