Which of the following scenarios describe an object being acted on by a non-conservative force? a. a puck hovers and glides across an air track at constant velocity. b. a dishwasher was pulled up to a window by a rope using a pulley system. c. a feather falls from one end of a tube to the other inside a vacuum. d. a charged particle was pushed away by another charged particle.

A puck hovers and glides across an air track at constant velocity is the scenario where a non-conservative force acts(air friction)

Explanation:

Conservative forces are the forces which are path-independent.

so, total work done by conservative forces in a closed loop is zero

Now, non-conservative forces are path-dependent forces.

These are dissipative forces in nature, so total work done by non-conservative forces is not zero.

Option a) A puck hovers and glides across an air track at constant velocity.

Even though puck moves with constant velocity there will air drag force which is friction and non-conservative in nature. so, to keep puck to move with constant velocity we need to compensate this friction.

Option b) A dishwasher was pulled up to a window by a rope using a pulley system.

Here, work is done against gravitational force which is conservative in nature.

Option c) A feather falls from one end of a tube to the other inside a vacuum.

Here, there are no forces. feather just moves in vacuum, so, the work done is also zero.

Option d) A charged particle was pushed away by another charged particle.

here, these are forces generated by electric charges, which are similar to gravitational force. so, these are also conservative forces.

the first successful, urban blues recording, selling more than 75,000 copies, was made in year 1920.

mamie smith recorded the first commercially successful example of the urban blues,   with the recording of “crazy blues”."crazy blues" was recorded on august 10, 1920, in new york city. within a month of the release of “crazy blues” it had sold 75,000 copies.

hi,

henry is an economist and wants to understand the relationship between inflation and consumer spending habits. for his research, he needs the consumer price index for 2014 and the inflation rate. based on the prices of goods given, what will he find to be the cpi and inflation rate for 2014? assume that a consumer’s basket for three consecutive years consists of the following:

you dont privide answer choices.

answer - 15% of a inflatation rate is 15% less in cpi