Lecture 3 (Center of Mass, Uniform Circular Motion, Torque, Equilibrium,Rotational Inertia)

Question 1

Center of Mass for Point Masses

Answer 1

x_cm= (m1x1 + m2x2 + m3x3…+ MX)/(m1+m2+m3…+M)

Question 2

Center of Gravity

Answer 2

is the point at which the total gravitational force on the system can be considered to act.

if gravity is constant then center of gravity=center of mass because g cancel

Question 3

Center of Gravity equation

Answer 3

X_CG= (w1x1 + w2x2 + w3x3…+ WX)/(w1+w2+w3…+ W)

Question 4

Uniform Circular Motion UCM

Answer 4

an object moving in a circular path is said to execute uniform circular motion if its speed is constant
velocity’s direction is always changing due to acceleration. velocity’s magnitude remains constant.

Question 5

Centripetal acceleration

Answer 5

the acceleration of an object undergoing UCM always points toward the center of the circle.

Question 6

Magnitude of Centripetal Acceleration

Answer 6

a_c= (V^2)/r

Question 7

Magnitude of Centripetal Force

Answer 7

F_c= m(a_c)= (mV^2)/r