Can work be done on a system if there is no motion?

1 ) Can work be done on a system if there is no motion? ( Yes, if an outside force is provided. Yes, since motion is only relative. ( ) No, since a system which is not moving has no energy ( ) No, because of the way work is defined. 2) If you walk 5 m horizontally forward at a constant velocity carrying a 10 N object, the amount of work done by the force holding up the object is ( ) > 50 J ( ) = 50 J ( ) < 50 J but more than OJ ( 0J 3) If the network done on an object is positive, then the objects kinetic energy () decreases ( ) remains the same() increases () is zero 4) An object hits a wall and bounces back with half of its original speed. What is the ration of the final kinetic energy to the initial kinetic energy? ( ) ( ) ( ) ( ) 4 5) Is it possible for a system to have negative potential energy? ( ) Yes, as long as the total energy is positive () Yes, since the choice of the zero of potential energy is arbitrary ( No, because the kinetic energy of a system must equal its potential energy ( No, because this would have no physical meaning. 6) A 0.2 kg mass attached to the end of a spring causes it to stretch 5 cm. If another 0.2 kg mass is added to the spring, the potential energy of the spring will be ( ) the same ( ) twice as much() 3 times as much () 4 times as much 7) You lift a 10 N book up in the air a distance of 1 m, at a constant velocity of 0.5 m/s. What is the work done by the weight of the book? ( ) +10 J ()-10 J ( ) +5J ()-5J 8) John pulls Jane in a sled on an icy surface (assume no friction), with a force of 60 N at an angle of 37° upward from the horizontal. If he pulls her a distance of 12 m, what is the work done by John? ( ) 185 J ( ) 433 J ( 575 J ( ) 720 J 9) When a car is braked to a stop, its kinetic energy is transformed to ( ) stopping energy ( ) potential energy ( ) energy of motion ( ) energy of rest () heat 10) Which has the greater kinetic energy, a car traveling at 30 km/h of a car of half the mass traveling at 60 km/h? ( the 30 km/h car ( the 60 km/h car ( both have the same kinetic energy 11) Which requires the most amount of work on the brakes of a car? () slowing down from 100 km/h to 70 km/h () slowing down from 70 km/h to a stop( both are the same 12) A horizontal force of 200 N is applied to move a 55 kg cart, initially at rest, across a 10 m level surface. What is the final speed of the cart? ( ) 73 m/s ( ) 36 m/s ( ) 8.5 m/s ( ) 6 m/s 13) A 400 N box is pushed up an inclined plane. The plane is 4 m long and rises 2 m. If the plane is frictionless, how much work was done by the push? ( ) 1600 J ( ) 800 J () 400 J ( ) 100 J 1 ) can perhaps work be achieved on a process if you have no movement? ( Yes, if some other energy is actually offered. Indeed, since movement is just family member. ( ) No, since a process in fact it is maybe not animated doesn’t have stamina ( ) No, due to the way job is described. 2) Should you walking 5 m horizontally forth at a consistent rate holding a 10 letter item, the quantity of efforts carried out by the energy supporting the thing is actually ( ) > 50 J ( ) = 50 J ( ) < 50 J but above OJ ( 0J 3) In the event the community accomplished on an object is actually good, then your item’s kinetic stamina () reduces ( ) continues to be the same() increase () is actually zero 4) An object strikes a wall and bounces right back with 1 / 2 of their initial rate. What’s the ration from the best kinetic stamina towards original kinetic stamina? ( ) ( ) ( ) ( ) 4 5) is it feasible for a process getting bad prospective stamina? ( ) Yes, providing the whole energy sources are good () Yes, considering that the selection of the zero of prospective energy sources are arbitrary ( No, since kinetic stamina of a process must equal their prospective stamina ( No, as this will have no real definition. 6) A 0.2 kg bulk connected to the conclusion of a spring leads to they to extend 5 cm. If another 0.2 kg bulk is actually put into the spring season, the possibility stamina from the spring season is ( ) the exact same ( ) doubly much() three times just as much () 4 occasions just as much 7) your raise a 10 letter guide right up floating around a distance of just one m, at a consistent rate of 0.5 m/s. What’s the efforts carried out by the extra weight from the guide? ( ) +10 J ()-10 J ( ) +5J ()-5J 8) John draws Jane in a sled on an icy area (believe no rubbing), with a force of 60 letter at an angle of 37° up from horizontal. If the guy draws the woman a distance of 12 m, what’s the efforts carried out by John? ( ) 185 J ( ) 433 J ( 575 J ( ) 720 J 9) whenever an automobile is actually braked to an end, their kinetic energy sources are altered to ( ) preventing stamina ( ) prospective stamina ( ) stamina of movement ( ) stamina of others () temperature 10) with the higher kinetic stamina, an automobile taking a trip at 30 km/h of an automobile of half the bulk taking a trip at 60 km/h? ( the 30 km/h vehicle ( the 60 km/h vehicle ( both have a similar kinetic stamina 11) Which necessitates the a lot of level of manage the brake system of an automobile? () reducing from 100 km/h to 70 km/h () reducing from 70 km/h to an end( both are identical 12) A horizontal energy of 200 letter is actually used on push a 55 kg cart, at first at peace, across a 10 m degree area. What’s the best rate from the cart? ( ) 73 m/s ( ) 36 m/s ( ) 8.5 m/s ( ) 6 m/s 13) A 400 letter container is actually forced right up an inclined flat. The flat is actually 4 m lengthy and increases 2 m. In the event the flat is actually frictionless, exactly how much efforts is carried out by the force? ( ) 1600 J ( ) 800 J () 400 J ( ) 100 J
KEf/KEi = (1/2)m(v/2)^2 / (1/2)mv^2
Last energizing stamina, KEf = (1/2)m*(v/2)^2
= 1/4
improvement in energizing stamina.
Jobs accomplished = Force*displacement
no efforts accomplished.
In the event the internet efforts accomplished on an item is actually good, after that item’s
  We understand that, KE = (1/2)mv^2
2) 0 J
kinetic energy sources are increase because efforts accomplished is understood to be a
3) increase
Preliminary kinetic stamina, KEi = (1/2)mv^2
4) 1:4
No job is accomplished since energy you may be applying isn’t for the
Today the rate is actually halved = v/2

If there’s no movement ways displacement is actually zero. Thus, there is certainly
1:4
1) No, due to the way job is described.
exact same movement where you is going.

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