Answer: Permanent magnets consist of multiple "ferromagnetic materials" I think that might be the answer, there weren't really any choices for me to choose from.
Answer:
Friction:-
The friction force is the force exerted by a surface as an object moves across it or makes an effort to move across it. There are at least two types of friction force - sliding and static friction. Though it is not always the case, the friction force often opposes the motion of an object. For example, if a book slides across the surface of a desk, then the desk exerts a friction force in the opposite direction of its motion. Friction results from the two surfaces being pressed together closely, causing inter molecular attractive forces between molecules of different surfaces. As such, friction depends upon the nature of the two surfaces and upon the degree to which they are pressed together. The maximum amount of friction force that a surface can exert upon an
EG:-
A coaster sliding against a table.
Gravity:-
The force of gravity is the force with which the earth, moon, or other massively large object attracts another object towards itself. By definition, this is the weight of the object. All objects upon earth experience a force of gravity that is directed "downward" towards the center of the earth. The force of gravity on earth is always equal to the weight of the object as found
EG:-
The force that causes a car to coast downhill even when you aren't stepping on the gas.
Elastic:-
Elasticity is the ability of a material to return to its original shape after being stretched or compressed. When an elastic material is stretched or compressed, it exerts elastic force. This force increases the more the material is stretched or compressed.
EG:-
An archer's stretched bow
Force is the agent which causes a change in the velocity of an object and thereby to acellerate it inertia on he other hand is a property which realtes to an intrinsic of a body to resist any change in its state rest or of emotion uniform or non uniform
Answer:
d). X-rays
Explanation:
X -rays are also called photons. They are a packet of electro magnetic radiation. X rays originate from the shell of the electron. X rays are highly penetrating, and have a shorter wavelength than alpha particles and the beta particles. They are similar to the gamma rays which are also has a high penetrating power and easily pass through the human body.
Thus X rays can penetrate a skin tissue upto 2 cm thickness.
