I need huge help understanding this type of questions :( Please and thank you The coefficient of static and kinetic frictions between a 15.2-kg box and a desk are 0.55 and 0.36, respectively. What is the net force on the box when a 120.9 N horizontal force is applied to the box while moving?

67.28 N

Explanation:

Given that,

The mass of an box, m = 15.2 kg

The coefficients of static and kinetic frictions for plastic on wood are 0.55 and 0.36, respectively.

The force of static friction,

The force of kinetic friction,

Net force acting on the object is :

F = 120.9 -53.62

= 67.28 N

Hence, this is the required solution.

heats surface water up

the minimum constant speed at which she can catch the train is 2.7 m/s

given:

acceleration = 0.6

time = 4.5 s

to find:

velocity = ?

formula used:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

solution:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

v = 0 + (0.6 × 4.5)

v = 2.7 m/s

the minimum constant speed at which she can catch the train is 2.7 m/s