1. two forces are applied to a box on a frictionless surface. one force is 40 n [s]. the second
force is 70 n in30 °w). what is the overall net force? (hint: you can figure out the answer without
any calculations.)
a) 40.6 n (s59.5 °e]
b) 110 n
c) 40.6 n [n59.5 °w]
d) 40.6 n

What type of electromagnetic wave is used in security pens? a. x-rays c. microwaves b. visible light d. ultraviolet radiation select the best answer from the choices provided

The most important difference between a wedge and an inclined plane is a. their size b. their shape c. how they are used d. what they are made of

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.