Prader-Willi syndrome is a disease that is present from birth (congenital). It affects many parts of the body. People with this condition feel hungry all the time and become obese. They also have poor muscle tone, reduced mental ability, and underdeveloped sex organs. Causes Prader-Willi syndrome is caused by a missing gene on chromosome 15. Normally, parents each pass down a copy of this chromosome. The defect can occur in a couple of ways: The father's genes are missing on chromosome 15 There are defects or problems with the fatherâs genes on chromosome 15 There are two copies of the mother's chromosome 15 and none from the father; These genetic changes occur randomly. Persons who have this syndrome usually do not have a family history of the condition. Symptoms Signs of Prader-Willi syndrome may be seen at birth.
Definition of momentum for English Language Learners. : the strength or force that something has when it is moving. : the strength or force that allows something to continue or to grow stronger or faster as time passes.
Angular Momentum. In Lesson 8, linear momentum (p) was defined as the objects mass (m) times its velocity (v) using the following equation: Angular momentum (L), is the quantity of rotation a body possesses. Angular momentum can be defined as the product of the objects moment of inertia (I) times its angular velocity (Ï). Angular momentum is calculated as follows: Where (L) is the angular momentum in units (kgâm 2 /s), (I) is the moment of inertia in kgâm 2, and (Ï) is the angular velocity in r/s. Angular momentum is a vector that is defined by the right hand rule. The direction of the angular momentum vector is the same as the direction of the angular velocity vector (CCW is positive, CW is negative). The units for linear momentum are kgÂ·m 2 /s.