Answer:

Explanation:
As we know that tank itself has mass given as 13.4 kg
so it is given as

also the tank contains air in it and the mass of air inside the tank is also given as 4.47 kg
so it is

so total mass of the tank is the mass of the empty tank and mass of air in the tank



Answer:
c. remains the same, but the RPMs decrease.
Explanation:
Because there aren't external torques on the system composed by the person and the turntable it follows that total angular momentum (I) is conserved, that means the total angular momentum is a constant:

The total angular momentum is the sum of the individual angular momenta, in our case we should sum the angular momentum of the turntable and the angular momentum of a point mass respect the center of the turntable (the person)
(1)
The angular momentum of the turntable is:
(2)
with I the moment of inertia and ω the angular velocity.
The angular momentum of the person respects the center of the turntable is:
(3)
with r the position of the person respects the center of the turntable, m the mass of the person and v the linear velocity
Using the fact
:
(3)
By (3) and (2) on (1) and working only the magnitudes (it's all that we need for this problem):


Because the equality should be maintained, if we increase the distance between the person and the center of the turntable (r), the angular velocity should decrease to maintain the same constant value because I and m are constants, so the RPM's (unit of angular velocity) are going to decrease.
Answer:
He is wrong!
Explanation:
Frequency refers to how many wave lengths pass in a second and speed is how fast the wave is traveling for example the speed of light goes really fast but has a mid-level frequency.
Hope this helps! ;-)
Answer:
v₂ = 17.98 m/s
Explanation:
given,
mass of ball = m = 4.6 Kg
length of string = L = 6.6 m
force acting toward the center is equal to the force exerted by centripetal acceleration


now, calculating the speed of ball at the bottom of the circlr
work done by the gravity = change in kinetic energy





v₂ = 17.98 m/s