The force of earth's gravitational field is always directed downwards (towards the center of the earth. When the ball is thrown up, it is going against the earth's gravitational field and so, the earth's gravitational force pulls it back down, accelerating it downwards.
Answer:
f = 8 N
Explanation:
Data provided in the question
Radius of the pulley = r = 0.05 m
Moment of inertia = (I) = 0.2 kg.m^{2}
Angular acceleration = ∝ = 2 rad/sec
Based on the above information
As we know that
Torque is


And,
Torque is also


So,
We can say that


0.05f = 0.4
f = 8 N
We simply applied the above formulas
I am quite sure the first one is Friction, but I am not sure about the second one. Is it wind?
The answer is Decibels. <span />
Wave D has the same wavelength as wave A, but the amplitude is lower. The answer is Wave D.