subject
Physics, 11.10.2019 03:30 leeshaaa17

Which of the following statements is(are) true?

(a) the total mechanical energy of a system, at any one instant, is either all kinetic or all potential energy.
(b) the total mechanical energy of a system is constant only if nondissipative interactions occur.
(c) the total mechanical energy of a system is constant only if dissipative interactions occur.
(d) the total mechanical energy of a system is equally divided between kinetic and potential energy.
(e) mechanical energy can be dissipated to nonmechanical forms of energy.

ansver
Answers: 3

Another question on Physics

question
Physics, 21.06.2019 22:00
Aroll in a paper machine is powered by a separately excited dc machine. operating point 1 (under load): the roll typically operates at 764 rpm and must provide 301 nm of torque to oppose the load of the paper. the armature voltage is 230v for this operating point operating point 2 (no load): when the load is removed the speed of the roll increases to 900 rpm (the field characteristics are unchanged) la ea dev m (a) calculate the maximum torque (units of nm) that the motor can supply with this applied voltage (b) calculate the value of the armature resistance, ra (in ohms) (c) at operating point 1 (loaded condition), the field current, i, and the total input power (armature field), are measured to be to be 10 a and 28,600 w respectively. use this information to calculate the value of the field resistance, rf (in ohms). (d) (d) at operating point 1 (loaded condition), calculate the motor efficiency. express your answer as a percent to at least 2 significant digits. (d) if the field voltage is reduced by 1/2, calculate the new stall torque (in nm) of the motor (f). if the field voltage is reduced by 1/2, calculate the new no-load speed (in rad/sec)
Answers: 1
question
Physics, 21.06.2019 22:50
A23 kg log of wood begins from rest, 300 m up a sluice (a water track used to transport logs, think of it as an inclined plane with negligible friction) inclined at 20° to the horizontal. after it reaches the flat waterway at the bottom it collides elastically with a 100 kg block of wood initially at rest near the base of the incline. (a) how long does it take the 23 kg log to travel down the incline? (b) what is the speed of the 23 kg log at the bottom of the incline? (c) what are the velocities of both blocks of wood after the collision? (d) what is the total kinetic energy before the collision? (e) what is the kinetic energy of the 23 kg log after the collision? (f) what is the kinetic energy of the 100 kg block of wood after the collision? (g) what is the total kinetic energy after the collision? (h) compare the total initial and total final kinetic energies. is this consistent with what you would expect for elastic collisions? explain!
Answers: 1
question
Physics, 22.06.2019 23:00
Which wave is the result of amplification and produces a louder sound
Answers: 1
question
Physics, 23.06.2019 02:00
Objects a and b are visible in the night sky. six months later they are still visible, but object b shows less parallax than object a. which object is closer? a. a b. b c. you would need to wait another six months in order to figure this out. d. you would need to know the objects' angular diameters in order to figure this out.
Answers: 3
You know the right answer?
Which of the following statements is(are) true?

(a) the total mechanical energy of a s...
Questions
question
Chemistry, 20.06.2020 15:57
question
Biology, 20.06.2020 15:57
question
Physics, 20.06.2020 15:57