10. Pressure, Gravity, and Moments

What is the SI unit of density?

• kg/m³

• kg/L

• N/m²

• g/cm³

What is the SI unit of pressure?

• kg

• m²

• N

• Pa

What is the formula for pressure in a liquid?

• P = 1/V

• P = ρgh

• P = F/A

• P = ρg/h

What does Boyle's Law state?

• Volume is inversely proportional to pressure

• Volume is directly proportional to temperature

• Volume is inversely proportional to temperature

• Volume is directly proportional to pressure

What is the value of the Universal Gravitation Constant G?

• 1.6 × 10^-19 C

• 6.7 × 10¹¹ N m^-2/kg²

• 9.8 m/s²

• 6.7 × 10^-11 N m²/kg²

What is the difference between static equilibrium and dynamic equilibrium?

• Static equilibrium involves no movement, dynamic equilibrium involves steady speed

• Static equilibrium involves acceleration, dynamic equilibrium does not

• Static equilibrium involves rotation, dynamic equilibrium does not

• Static equilibrium involves no forces, dynamic equilibrium involves forces

What are the two conditions necessary for the equilibrium of a set of co-planar forces?

• Equal forces and opposite directions

• Zero net force and zero net moment

• Equal net force and equal net moment

• Zero net force and opposite directions

What is the moment of a force?

• Force multiplied by the angle between lever and the fulcrum or axis of rotation

• Force multiplied by the parallel distance from fulcrum or axis of rotation

• Force divided by perpendicular distance from fulcrum or axis of rotation

• Force multiplied by perpendicular distance from fulcrum or axis of rotation

What is a couple in physics?

• Two perpendicular forces with different magnitudes pointing in the same direction and acting about the same axis of rotation

• Two parallel forces with different magnitudes pointing in the same direction and acting about the same axis of rotation

• Two parallel forces with the same magnitude pointing in opposite directions and acting about the same axis of rotation

• Two perpendicular forces with the same magnitude pointing in opposite directions and acting about the same axis of rotation

What is the moment of the couple exerted on the stick shown?

• 200 N m

• 400 N m

• 240 N m

• 320 N m