Answer
given,
Tension of string is F
velocity is increased and the radius is not changed.
the string makes two complete revolutions every second
consider the centrifugal force acting on the stone
=
now centrifugal force is balanced by tension
T =
From the above expression we can clearly see that tension is directly proportional to velocity and inversely proportional to radius.
When radius is not changing velocity is increasing means tension will also increase in the string.
Answer:
a) 3-in. pipe
Explanation:
Given that
Fluid flow is in same amount in the same time it means that volume flow rate is same for the pipes
Volume flow rate
Q = A V
A=Area ,V=Velocity

If diameter d is more then the velocity will be less for same volume flow rate .We also Know that if pressure is more then the velocity will be less.
The second pipe 3 in diameter having more diameter then the velocity will be less but the pressure will be more.
That is why the 3 in diameter is having more pressure than 2 in diameter pipe.
Therefore the answer will be a.
a) 3-in diameter pipe
An opera singer breaks a thin glass with only the use of her high frequency voice
“Charged objects have an imbalance of charge - either more negative electrons than positive protons or vice versa. And neutral objects have a balance of charge - equal numbers of protons and electrons. The principle stated earlier for atoms can be applied to objects. Objects with more electrons than protons are charged negatively; objects with fewer electrons than protons are charged positively.
In this discussion of electrically charged versus electrically neutral objects, the neutron has been neglected. Neutrons, being electrically neutral play no role in this unit. Their presence (or absence) will have no direct bearing upon whether an object is charged or uncharged. Their role in the atom is merely to provide stability to the nucleus.”
Hope this helps a bit.
!! (Credits to The Psychics Classroom) !!
Answer:
V = 2.87 m/s
Explanation:
The minimum speed required would be that at which the acceleration due to gravity is negated by the centrifugal force on the water.
Thus, we simply need to set the centripetal acceleration equal to gravity and solve for the speed V using the following equation:
Centripetal acceleration = V^2 / r
where r is the distance of water from the pivot or shoulder.
For our case, r will be 0.65 + 0.19 = 0.84 m
and solving the above equation we get:
9.81 = V^2 / 0.84
V^2 = 8.2404
V = 2.87 m/s