According to newton's third law of motion, when a hammer strikes and exerts force to push it into a piece of wood, the nail <span>C. exerts an equal or opposite force on the hammer. The third law of motion states that every action has an equal BUT opposite reaction. This means that the nail exerts the same force the hammer exerts on it.</span>
Answer:
(A) She needs to move the decimal point by 3 places
Answer:
a)
& 
b) 
c) 
Explanation:
Given:
mass of the book, 
combined mass of the student and the skateboard, 
initial velocity of the book, 
angle of projection of the book from the horizontal, 
a)
velocity of the student before throwing the book:
Since the student is initially at rest and no net force acts on the student so it remains in rest according to the Newton's first law of motion.

where:
initial velocity of the student
velocity of the student after throwing the book:
Since the student applies a force on the book while throwing it and the student standing on the skate will an elastic collision like situation on throwing the book.

where:
final velcotiy of the student after throwing the book
b)



c)
Since there is no movement of the student in the vertical direction, so the total momentum transfer to the earth will be equal to the momentum of the book in vertical direction.



Answer:
D. creates radioactive waste.
Explanation:
Nuclear energy can create nuclear radioactive waste
Answer:
<em>The new period of oscillation is D) 3.0 T</em>
Explanation:
<u>Simple Pendulum</u>
A simple pendulum is a mechanical arrangement that describes periodic motion. The simple pendulum is made of a small bob of mass 'm' suspended by a thin inextensible string.
The period of a simple pendulum is given by

Where L is its length and g is the local acceleration of gravity.
If the length of the pendulum was increased to 9 times (L'=9L), the new period of oscillation will be:


Taking out the square root of 9 (3):

Substituting the original T:

The new period of oscillation is D) 3.0 T