a force of 9.0N is applied to a body at rest on a smooyh horizontal surface. if the body has a mass of 18.0kg and it moves in the direction of the force, find the work done in; (a) the first four second (b) the fourth second.

Answer 1

What is the acceleration? Force = mass * acceleration; thus, acceleration = force/mass = 9N/18 kg = ½ meters/second^2

we also know that distance-traveled = initial displacement + time * initialVelocity + (acceleration * time^2)/2

because initial displacement = 0, and initialVelocity = 0, then distance-traveled = (acceleration * time^2)/2 = (½ * 4^2)/2 = 4 meters

Then Work = Force * distance = 9 N * 4 meters = 36 Newton meters

Answer 2

I copied this work from
www.quora.com/A-force-of-9-0-newtons-is-applied-to-a-body-at-rest-on-a-smooth-horizontal-surface-If-the-body-has-a-mass-of-18-0-kg-and-it-moves-in-the-direction-of-the-force-what-is-the-work-done-in-4-seconds