Quantum theory is the theoretical basis of modern physics that explains the nature and behavior of matter and energy on the atomic and subatomic level. Planck wrote a mathematical equation involving a figure to represent these individual units of energy, which he called quanta.
Quantum mechanics [QM] is a branch of physics which describes physical systems so that properties like the energy or angular momentum are discrete quantities that are multiples of a smallest unit or quantum. A famous physicist named Erwin Schrödinger made an example of quantum mechanics, often called Schrödinger's cat.
A potter’s wheel moves from rest to an angular speed of 0.10 rev/s in 20.2 s. Assuming constant angular acceleration,
what is its angular acceleration in rad/s^2?
Answer in units of rad/s
ω₀ = 0 rad/s
ω = 0.10 rev/s = 0.628 rad/s
t = 20.2 s
ω = αt + ω₀
0.628 rad/s = α (20.2 s) + 0 rad/s
α = 0.031 rad/s²
Imagine a place in the cosmos far from all gravitational and frictional influences. Suppose that you visit that place (just suppose) and throw a rock. What will the rock do? Why?
In a place in the cosmos from all gravitational and frictional influences, when you throw a rock, the rock will just float. If the rock is far from any object in space, it will not be attracted to it due to gravitational attraction. This is because in space, there is an absence of gravity.
a 0.4 kg block rests on a desk. the coefficient of static friction is 0.2. You push the side of the block but do not have a spring scale to measure the force you use. the block does not move. which statement is true about the force of static friction?
D. It is no smaller than
The question is incomplete. These are all the options :
A. It is no larger than
B. It is
C. It is
D. It is no smaller than
To solve this problem, we have the data of :
Where ''m'' is the mass of the block
μ = 0.2
Where ''μ'' is the coefficient of static friction
If we want to find the magnitude of the force of static friction we need to use the following equation :
Where '''' is the normal force that the desk exerts on the block. Its magnitude is equal to the weight (because we suppose that the block rests horizontally on the desk).
The weight '''' can be calculated as :
Where ''m'' is the mass and ''g'' is the acceleration due to gravity.
The value of ''g'' is
The weight of the block is
Now, the weight is equal to the normal force ⇒
Using the equation (I) :
The correct option is D. It is no smaller than
In preparation for an electrophoresis procedure, enzymes are added to DNA in order to 1.) Convert the DNA into gel
2.) Cut the DNA into fragments
3.) Change the color of the DNA
or 4.) Produce longer sections of DNA
In preparation for an electrophoresis procedure, enzymes are added to DNA in order to cut the DNA into fragments. Thus, option B is correct.What do you mean by Gel electrophoresis?
Gel electrophoresis may be defined as a biotechnical laboratory procedure operated to isolate mixtures of DNA, RNA, or proteins according to their molecular size.
Enzymes known as restriction endonucleases are added to the DNA during the process of gel electrophoresis in order to cut the DNA into numerous fragments and isolate them according to their molecule weight.
Therefore, in preparation for an electrophoresis procedure, enzymes are added to DNA in order to cut the DNA into fragments. Thus, option B is correct.
To learn more about Gel electrophoresis, refer to the link: