Answer:
Work, in physics, measure of energy transfer that occurs when an object is moved over a distance by an external force
Explanation:
at least part of which is applied in the direction of the displacement. ... To express this concept mathematically, the work W is equal to the force f times the distance d, or W = fd.
Answer:
v_f = 10.85 m/s
Explanation:
We will apply the law of conservation of momentum here:

where,
m₁ = mass of roller skater = 47 kg
m₂ = mass of bag = 6 kg
v_1i = initial speed of roller skater = 12 m/s
v_2i = initial speed of the bag = 0 m/s
v_1f = final speed of the roller skater = ?
v_2f = final speed of the bag = ?
Both the bag and the skater will have same speed at the end because kater is carrying the bag:
v_1f = v_2f = v_f
Therefore, the equation will become:

<u>v_f = 10.85 m/s</u>
Positive Work.
Negative Work.
Case of zero work done.
Displacement at an angle to the force.
Energy.
Kinetic Energy.
work is the energy transferred to or from an object via the application of force along a displacement. In its simplest form, it is often represented as the product of force and displacement.
Well, F = ma
and a= change in vel / change in time
= (2-0 ) / 1 = 2 m^2/s
so, F= 4* 2 = 8 N
and W = F.S = 8 * 2 = 16 J
hope it helped