Answer:
If the system consists of the block only, the work done by the gravity is negative.
If the system consists of the block and the earth the work done by the gravity is zero.
Explanation:
If the system consists of the block only, then the system experiences two external forces: one exerted by the hand that lifts the block vertically upward and other exerted by the earth (gravity), which is opposed to the movement of the system, so the work done by gravity is negative.
On the other hand, if the system consists of the block and the earth, then only exists a external force which is the exerted by the hand. So, the force exerted by gravity is zero.
Answer:
The correct answer is D. Electrons in an atom that can bond with other atoms.
Explanation:
For those of you that need it still
An object need to move in a straight line in the same direction in equal intervals of time in order for total distance traveled and displacement to be equal.
Answer:
n = 1.76
Explanation:
According to the rule of ( n1 sin theta1 = n2 sin theta2 )
we know both angles so we insert them to the law and apply n1 = 1
so 1/2 = n2 sin 62 and we get the final answer
