Which statement about van der waals forces is true? multiple
a. when the forces are weaker, a substance will have higher volatility.
b. when the forces are stronger, a substance will have lower viscosity.
c. when the forces are weaker, the boiling point of a substance will be higher.
d. when the forces are stronger, the melting point of a substance will be lower.

The step-down transformer gives a current of 10a at 24v if the primary voltage is 240v calculate the 1_primary current 2_the power input 3_the power output

Consider an ordinary, helium-filled party balloon with a volume of 2.2 ft3. the lifting force on the balloon due to the outside air is the net resultant of the pressure distribution exerted on the exterior surface of the balloon. using this fact, we can derive archimedes’ principle, namely that the upward force on the balloon is equal to the weight of the air displaced by the balloon. assuming that the balloon is at sea level, where the air density is 0.002377 slug/ft3, calculate the maximum weight that can be lifted by the balloon. note: the molecular weight of air is 28.8 and that of helium is 4.

Heterogeneous mixture with larger particles that never settle is