A substance maintaining a uniform appearance throught is called homogeneous
Newton's 2nd law of motion: Force = (mass) x (acceleration)
If you want to move a 7-kg object with an acceleration of 6 m/s²,
then you will need to push it with (7 x 6) = 42 newtons of force.
You don't mean the force of an object.
Answer:What is the first law of thermodynamics and how does it relate to energy use? The first law of thermodynamics states that energy is conserved in chemical processes. ... This amount of energy that must be lost to the surroundings for the process to occur is nature's heat tax, an unavoidable cut of every energy transaction.
Explanation:
Answer
given,
position of particle
x(t)= A t + B t²
A = -3.5 m/s
B = 3.9 m/s²
t = 3 s
a) x(t)= -3.5 t + 3.9 t²
velocity of the particle is equal to the differentiation of position w.r.t. time.

------(1)
velocity of the particle at t = 3 s
v = -3.5 + 7.8 x 3
v = 19.9 m/s
b) velocity of the particle at origin
time at which particle is at origin
x(t)= -3.5 t + 3.9 t²
0 = t (-3.5 + 3.9 t )
t = 0, 
t = 0 , 0.897 s
speed of the particle at t = 0.897 s
from equation (1)
v = -3.9 + 7.8 t
v = -3.9 + 7.8 x 0.897
v = 3.1 m/s