Answer:
1. The force of the shelf holding the book up.
Explanation:
The free body diagram of the book is as follows:
1 - The weight of the book towards downwards
2 - The normal force that the shelf exerts on the book towards upwards.
Since the book is at rest, these two forces are equal to each other and according to Newton's Third Law the reaction force to the force of gravity is equal but opposite to the weight of the book. This reaction force is the one that holds the book up on the shelf.
Answer:
When a an object is been rotated its resistance capacity to that rotational force is know as rotational inertia and this mathematically given as

Where m is the mass
r is the rotation radius
For the spinning of the lamp as a baton to work the location of the center of mass of the floor lamp needs to be located
This is more likely to be located closer to base of the lamp as compared to the top, so success of spinning a floor lamp like a baton is highly likely if the lamp is grabbed closer to the base because that is where the position of its center of mass is likely to be.
Explanation:
Complete Question
The complete question is shown on the first uploaded image
Answer:
The correct answer is option c
Explanation:
Faraday states that when there is a change in magnetic field of a coil of a wire, it means that there exist an emf in the circuit which in induced due to the change in the magnetic flux
From the question two separate but nearby coils are mounted along the axis. First coil is connected to the power supply and the current flow is controlled by the supply.When the current alternates, it would produce magnetic field ,also the second coil is connected to an ammeter which indicates the current that is flowing in it when current in the first coil changes
This magnetic field that is produce would cause a change flux which would induce current in the second coil so the ammeter would indicate current flow in the second coil
a is incorrect because the current in fir coil is not change hence flux won't change therefore current is is not induced in second coil
This is the same reason b is incorrect
d is incorrect due to the fact that when the second coil is connected to a power supply by rewiring it to be in series with first coil the law of electromagnetism would no longer hold so he ammeter would show no reading
Answer:
1.6 s
Explanation:
To find the time in which the potential difference of the inductor reaches 24V you use the following formula:

V_o: initial voltage = 60V
R: resistance = 24-Ω
L: inductance = 42H
V_L: final voltage = 24 V
You first use properties of the logarithms to get time t, next, replace the values of the parameter:

hence, after 1.6s the inductor will have a potential difference of 24V