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.
Able to be hammered or pressed permanently out of shape without breaking or cracking.
a)
for the puck :
F = force applied in the direction of pull
N = normal force on the puck in upward direction by the surface of table
W = weight of the puck in down direction due to force of gravity
b)
along the vertical direction , normal force balance the weight of the puck , hence the net force is same as the force of pull F .
so F = ma where m = mass of puck , a = acceleration
Fnet = F
c)
since the net force acts in the direction of force of pull F , hence the puck accelerates in the same direction .
<span>In order for
an object to accelerate, a <u>force</u> must be applied. It follows Newton’s second
law of motion where it states that a body at rest remains at rest unless a
force is acted upon it. When you move an object, you are exerting a force onto
it. By exerting a force on the object, you are actually displacing it from its
initial position. You cannot apply force to the object without altering its
position. Keep in mind that when you exert work, you are exerting energy too. </span>
