Answer:
Cause its scalar quantity
Explanation:
since speed does not take directions into consideration, it is considered to be a scalar quantity. On the other hand, the velocity of an object does not take into account direction, thus making it a vector quantity.
Answer: option A) initially increases, then decreases.
Justification:
The increase of the rate of effective collisions among particles as the temperature increases is explained by the collision theory in virtue of the increase of the kinetic energy.
This is, as the temperature increase so the kinetic energy increase and the higher the kinetic energy the greater the number of collisions and the greater the chances that this energy overcome the activation energy (the energy needed to start the reaction).
Now, as the reaction progress the number of reactants particles naturally decrease (some of them have been converted into product) so this lower number of particles means lower concentration which means lower collisions and, thereafter, a decrease in the reaction rate.
Answer:
Explanation:
Pressure is equal to the force divided by the area on which it acts. Since the smaller piston has less area so from less force also we can get more efficiency in work. And according to the Pascal's principle, in a hydraulic system, pressure exerted on a piston produces an equal increase in pressure on another piston in the system. Thus by applying little force in the smaller piston, we can get same force from larger piston too. A hydraulic machine magnifies force.
Answer: The force of attraction that holds two molecules is a chemical bond
Explanation:
What is Chemical bonds?
Chemical bonds are forces that hold atoms together to make compounds or molecules.
Types of chemical bonds
Chemical bonds include
1.covalent,
2. polar covalent, and
3. ionic bonds.
Atoms with relatively similar electronegativities share electrons between them and are connected by covalent bonds.
Answer:
'Incident rays that are parallel to the central axis are sent through a point on the near side of the mirror'.
Explanation:
The question is incomplete, find the complete question in the comment section.
Concave mirrors is an example of a curved mirror. The outer surface of a concave mirror is always coated. On the concave mirror, we have what is called the central axis or principal axis which is a line cutting through the center of the mirror. The points located on this axis are the Pole, the principal focus and the centre of curvature. <em>The focus point is close to the curved mirror than the centre of curvature.</em>
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During the formation of images, one of the incident rays (rays striking the plane surface) coming from the object and parallel to the principal axis, converges at the focus point after reflection because all incident rays striking the surface are meant to reflect out. <em>All incident light striking the surface all converges at a point on the central axis known as the focus.</em>
Based on the explanation above, it can be concluded that 'Incident rays that are parallel to the central axis are sent through a point on the near side of the mirror'.
