When we rub balloon on a shirt the balloon will steal electrons from the shirt and the shirt will become positively charged and balloon will negatively charged.<span>The reason that the balloon will stick to the wall is because the negative charges in the balloon will make the electrons in the wall move to the other side of their atoms and this leaves the surface of the wall positively charged.</span>
Musical instruments use resonance to amplify the sound and make the sounds louder
Answer: a) angular acceleration(alpha)=-14.8rad/s^2
b) time taken (t) = 1.52s
Explanation:
What we are given
Mass of the solid sphere m =225g = 0.225kg
Diameter D = 3.00cm = 0.0300m
Radius = D/2 = 0.01500m
Frictional Force = 0.0200N
a) to determine the angular acceleration, we first calculate the torque, then moment of inertia, before the angular acceleration.
Torque = -fr
= - (0.0200)(0.01500)
=-3.00X10^-4Nm
Moment of inertia I
= 2/5mr^2
=2/5(0.225)(0.01500)^2
=2.025X10^-5kgm^2
Angular acceleration (alpha)= torque/moment of inertia (I)
= -3.00X10^-4Nm/2.025X10^-5kgm^2
=-14.8rad/s^2
b) time taken (∆t) = w/alpha
w= -22.5rad/s
Angular acceleration (alpha) = -14.8rad/s^2
∆t = -22.5/-14.8
= -1.52s