Answer:
Between the principal focus and the pole of the mirror
The answer is B. Unbalanced force
Answer with Explanation:
We are given that
Mass of spring,m=3 kg
Distance moved by object,d=0.6 m
Spring constant,k=210N/m
Height,h=1.5 m
a.Work done to compress the spring initially=
b.
By conservation law of energy
Initial energy of spring=Kinetic energy of object



v=5.02 m/s
c.Work done by friction on the incline,

If we use the equation:
N2 + 3H2 --> 2NH3
Then
1 mol of Nitrogen required 3 moles of Hydrogen
x mols : 6.34mols
X = 6.34/3
X = 2.11 moles of Nitrogen are required.
Answer:
The answer to your question: d.
Explanation:
a. The rate of change of momentum of an object is equal to the net force applied to the object.
This is the second a law of motion, so this answer is incorrect.
b. In the absence of a net force acting on it, an object moves with constant velocity.
This is the first Newton law of motion, so this option is not correct.
c. For any force, there always is an equal and opposite reaction force.
This is the third law of motion, so this is not the right option.
d. What goes up must come down.
Newton said this sentence, but is not part of the law of motion.