DEFINITION of 'Human Development Index-HDI'. A tool developed by the United Nations to measure and rank countries' levels of social and economic development based on four criteria: Life expectancy at birth, mean years of schooling, expected years of schooling and gross national income per capita.EFINITION of 'Human Development Index-HDI'. A tool developed by the United Nations to measure and rank countries' levels of social and economic development based on four criteria: Life expectancy at birth, mean years of schooling, expected years of schooling and gross national income per capita.
A top and bottom gear rack are moving in the same direction but with different velocities (top rack 5 m/s and bottom rack 3 m/s). What is the angular velocity of the small attached gear B at the instant shown? Assume the top rack, bottom rack, and link AB remain horizontal.
Meters per second. The SI measurement of speed and velocity. This is the number of meters travelled in one second of time. The accompanying acceleration unit is meters per second per second (m/sÂ²). This is a measurement of speed typically used in non-metric countries for transport such as the USA.