Explanation:
The dimension of the book is 1.75 m × 2.25 m. If the book ends up at its initial position. The displacement of the book is equal to zero as the object reaches to its initial position.
If it completes its motion in 23 s, t = 23 s
Total displacement of the book is equal to its perimeter. It is given by :

The net displacement divided by total time taken is called the average velocity of an object. Here, the displacement is 0. So, average velocity is 0.
The average speed of an object is given by :


v = 0.347 m/s
So, the average speed of the book is 0.347 m/s. Hence, this is the required solution.
Answer:
The force of gravity exerts a downward force. The floor exerts an upward force. Since these two forces are of equal magnitude and in opposite directions, they balance each other.
In a nuclear power plant, energy is released from the nuclei of atoms. The correct option among all the options given in the question is the first option. Huge amount of thermal energy is released by the breaking of the uranium atoms. This energy is used for turning a turbine that produces electricity. It is a very clean method of producing electricity.
Answer:
D)Not enough information
Explanation:
According to Pascal's principle, the pressure exerted on the two pistons is equal:

Pressure is given by the ratio between force F and area A, so we can write

The force exerted on each piston is just equal to the weight of the corresponding mass:
, where m is the mass and g is the gravitational acceleration. So the equation becomes

Now we can rewrite the mass as the product of volume, V, times density, d:

We also know that 
So we can further re-arrange the equation (and simplify g as well):


We are also told that block B has bigger volume than block A:
. However, this information is not enough to allow us to say if the fraction on the right is greater than 1 or smaller than 1: therefore, we cannot conclude anything about the densities of the two objects.
theanswer is b.heart disease