សិស្សម្នាក់លើកសៀវភៅ 1 ក្បាល ពីក្តារក្រាលដាក់លើធ្វើទូរសៀវភៅមួយ កម្ពស់ 2 m ដោយបញ្ចេញកម្មន្ត 10 ] ។ ដោយសន្មតថាសំទុះទំនាញដីគឺ
10 m/s ម៉ាសរបស់សៀវភៅនោះគឺ៖

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.

Aboat radioed a distress call to a coast guard station. at the time of the call, a vector a from the station to the boat had a magnitude of 45.0 km and was directed 15.0° east of north. a vector from the station to the point where the boat was later found is = 30.0 km, 15.0° north of east. what are the components of the vector from the point where the distress call was made to point where the boat was found? in other words, what are the components of vector c = b - a?

What kind of simple machine is a catapult?