One end of a horizontal spring with force constant 130.0 n/m is attached to a vertical wall. a 4.00-kg block sitting on the floor is placed against the spring. the coefficient of kinetic friction between the block and the floor is μk = 0.400. you apply a constant force f, which is directed toward the wall. f has magnitude of 82.0 n and is directed toward the wall. at the instant that the spring is compressed 80.0 cm, what are(a) the speed of the block, and(b) the magnitude and direction of the block's acceleration?

Answer

given,

force constant = 130 N/m

mass of block = 4 kg

μk = 0.400

magnitude of force = 82 N

compressed to the distance of (x) = 80 cm = 0.8 m

using conservation of energy

v=2.39 m/s

Net force on the block is

            = 82 - 0.4×4×9.8 - 130×0.8

            = -37.68 N

Acceleration of the block

a =9.42 m/s²

the box does not move because you need to use a force greater than 300 n. you are only using 50 n. it needs to at least be 301 n for the box to move because then it is an unbalanced force and it will move the way that the greater force is pushing it. if you use only 300 n it will be a balanced force and will not move because the force you are exerting on the   box is the same as its force.

hope this !

im sorry if i went too in depth, i am going to include a link to a video on khan academy that will explain this.   hope that you like the video and that it explains more in detail to you.

that is the link.

d₁ = displacement of tern from arctic to antarctic = 11000 miles

d₂ = displacement of tern from antarctic to arctic =   - 11000 miles

d = total displacement for the journey

total displacement for the journey is given as

d = d₁ + d₂

d = 11000 + (-11000)

d = 0 miles

t₁ = time of travel from arctic to antarctic = 3 months = 3 x 30 days = 90 days

t₂ = time of travel from antarctic to arctic = 3 months = 3 x 30 days = 90 days

t = total time of travel

total time of travel is given as

t = t₁ + t₂

t = 90 + 90

t = 180 days

average velocity is given as

average velocity = total displacement/ total time

v = d/t

v = 0/180

v = 0 miles/day