Physics, 17.03.2020 04:41 hallkanay7398
An engineer is designing a spring to be placed at the bottom of an elevator shaft. If the elevator cable breaks when the elevator is at a height h above the top of the spring, calculate the value that the spring constant k should have so that passengers undergo an acceleration of no more than 7.0 g when brought to rest. Let M be the total mass of the elevator and passengers. Express your answer in terms of the variables h, M, and appropriate constants.
k = ?
Answers: 3
Physics, 22.06.2019 00:00, angelequej1167
Which is not a characteristic of a heat pump? a. it is used in air conditioners. b. it uses a refrigerant. c. it requires no work. d. it reverses the normal flow of thermal energy.
Answers: 2
Physics, 22.06.2019 00:30, powberier6979
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.
Answers: 2
Physics, 22.06.2019 15:30, tiffuuu
At 20∘c, the hole in an aluminum ring is 2.800 cm in diameter. you need to slip this ring over a steel shaft that has a room-temperature diameter of 2.804 cm . 1. to what common temperature should the ring and the shaft be heated so that the ring will just fit onto the shaft? coefficients of linear thermal expansion of steel and aluminum are 12×10−6 k−1 and23×10−6 k−1 respectively.
Answers: 1
Physics, 22.06.2019 18:30, jonathanvega424
Asmall 12.00g plastic ball is suspended by a string in a uniform, horizontal electric field with a magnitude of 10^3 n/c. if the ball is in equilibrium when the string makes a 30 ° angle with the vertical, what is the net charge on the ball?
Answers: 1
An engineer is designing a spring to be placed at the bottom of an elevator shaft. If the elevator c...
Geography, 12.10.2020 19:01
Social Studies, 12.10.2020 19:01
Mathematics, 12.10.2020 19:01
Mathematics, 12.10.2020 19:01
Mathematics, 12.10.2020 19:01
French, 12.10.2020 19:01