Answer:
20 J
Explanation:
Given:
Weight of the book is, 
Height or displacement of the book is, 
The work done on the book to raise it to a height of 2 m on a shelf is against gravity. The gravitational force acting on the book is equal to its weight. Now, in order to raise it, an equal amount of force must be applied in the opposite direction.
So, the force applied by me should be equal to weight of the body and in the upward direction. The displacement is also in the upward direction.
Now, work done by the applied force is equal to the product of force applied and displacement of book in the direction of the applied force.
Therefore, work done is given as:
Therefore, the work done to raise a book to a height 2 m from the floor is 20 J.
Ionic bonding is a type of chemical bonding that involves the electrostatic attraction between oppositely charged ions, and is the primary interaction occurring in ionic compounds.A covalent bond, also called a molecular bond, is a chemical bond that involves the sharing of electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs, and the stable balance of attractive and repulsive forces between atoms, when they share electrons, is known as covalent bonding.
B. Wrap more coils of wire around the nail
Increasing the number of coils in an electromagnet increases the strength of the magnetic field.
Answer:
Mass of Little Sister = 44.17 kg
Explanation:
From Newton's second law of motion, the magnitude of force applied on the sled is given by the following formula:
F = ma
where,
F = Force Applied = 120 N
a = Acceleration = 2.3 m/s²
m = Mass of Sled + Mass of Little Sister = 8 kg + Mass of Little Sister
Therefore,
120 N = (2.3 m/s²)(8 kg + Mass of Little Sister)
(120 N)/(2.3 m/s²) = 8 kg + Mass of Little Sister
Mass of Little Sister = 52.17 kg - 8 kg
<u>Mass of Little Sister = 44.17 kg</u>
