Answer:
35.6 N
Explanation:
We can consider only the forces acting along the horizontal direction to solve the problem.
There are two forces acting along the horizontal direction:
- The horizontal component of the pushing force, which is given by
with 
- The frictional force, whose magnitude is
where 
, m=8.2 kg and g=9.8 m/s^2.
The two forces have opposite directions (because the frictional force is always opposite to the motion), and their resultant must be zero, because the suitcase is moving with constant velocity (which means acceleration equals zero, so according to Newton's second law: F=ma, the net force is zero). So we can write:
Quantum theory is the theoretical basis of modern physics that explains the nature and behavior of matter and energy on the atomic and subatomic level. The nature and behavior of matter and energy at that level is sometimes referred to as quantum physics and quantum mechanics.
Answer:
Natural selection is a mechanism, or cause, of evolution.
Explanation:
Adaptations are physical or behavioral traits that make an organism better suited to its environment. Heritable variation comes from random mutations.
Answer:
D
friction acts in the opposite direction of motion but does not affect the motion of the object
