]A net force of 15 N is applied to a cart with a mass of 2.1 kg. How long will it take the cart to travel 2.8 m, starting from rest? Acceleration=7.14m/s²

we will use one of the kinematic equations :

d = u*t+0.5*a*t²

in which : d : distance

u : initial velocity

a : acceleration

t : time

after substitution :

initial velocity = 0 m/s (from rest)

2.8 = 0*t+0.5*7.14*t²

2.8 = 3.57*t²

t² = 0.7843

after square root

t = 0.885615 s

I hope this answer will help

freezing

deposition

condensation

explanation;

melting also called fusion is the process where solid becomes liquid, sublimation is the process where solid becomes gaseous without first changing to liquid, deposition involves change from gaseous to solid state, freezing involves change from liquid to solid, boiling or evaporation involves change of liquid to gaseous state, while condensation is the change from gaseous state to liquid state.

endothermic reactions involves absorption of heat from the surroundings or the environment while exothermic reactions involves loss of heat energy to the surroundings.

in this case, sublimation, evaporation and melting are endothermic reactions (gain energy from the environment) while, freezing, deposition and condensation are exothermic (loss of energy to the surroundings) reactions.

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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