Answer:
IMA = 2.5 metres
EFFICIENCY = 80%
Explanation:
The AMA of a machine is referred to as the Actual Mechanical Advantage of a machine, calculated as the ratio of the output to the input force.
The Ideal Mechanical Advantage is the ratio of the input distance to the output distance.
From the diagram, the input distance which is also the distance moved by effort = 5metres
The load distance (output distance) = 2 metres
IMA = INPUT DISTANCE / OUTPUT DISTANCE
IMA = 5metres / 2 metres = 2.5 meters
Efficiency is the ratio of AMA TO IMA
AMA = 2, IMA = 2.5
EFFICIENCY = AMA / IMA
EFFICIENCY = (2 / 2.5) × 100%= 0.8 × 100%
EFFICIENCY = 80%
That's unaccelerated motion,
and constant velocity.
Answer:
(a) 
(b) 
Explanation:
Hello.
(a) In this case since the car is moving at an initial velocity of 18 m/s due north, the final velocity is computed considering the acceleration as positive since it is due north as well:

(b) In this case, since the car is moving due north by the acceleration is due south it is undergoing a slowing down process, thereby the acceleration is negative therefore the final velocity turns out:

Best regards.