In accordance with the definition of density as r = m/V, in order to determine the density of
matter, the mass and the volume of the sample must be known.
The determination of mass can be performed directly using a weighing instrument.
The determination of volume generally cannot be performed directly. Exceptions to this rule
include
· cases where the accuracy is not required to be very high, and
· measurements performed on geometric bodies, such as cubes, cuboids or cylinders, the volume
of which can easily be determined from dimensions such as length, height and diameter.
· The volume of a liquid can be measured in a graduated cylinder or in a pipette; the volume of
solids can be determined by immersing the sample in a cylinder filled with water and then
measuring the rise in the water level.
Because of the difficulty of determining volume with precision, especially when the sample has a
highly irregular shape, a "detour" is often taken when determining the density, by making use of the
Archimedean Principle, which describes the relation between forces (or masses), volumes and
densities of solid samples immersed in liquid:
From everyday experience, everyone is familiar with the effect that an object or body appears to
be lighter than in air – just like your own body in a swimming pool.
Figure 3: The force exerted by a body on a spring scale in air (left) and in water (right)
Answer:
The first law of thermodynamics is the law of conservation of energy. It states that energy is always conserved. ... To keep a machine moving, the energy applied should stay with the machine without any losses. Because of this fact alone, it is impossible to build perpetual motion machines.
Explanation:
A motorboat accelerates uniformly from a velocity of 6.5m/s
to the west to a velocity of 1.5m/s to the west. if its accelerate was 2.7m/s2
to the east ,
how far did it travel during the accelration? Give your
answer in units of kilometers per hour/sec. To find the acceleration of the car
we have to
<span>
1. First determine
the suitable formula for this word problem.
Which is a. A=vf-vi/t</span>
which will be
Given are: Vi= 6.5 m/s Vf= 1.5 m/s a= 2.7 m/sec2 t=1.85s
Solution:
<span>
x = v0t + ½at2</span>
<span>x = <span>16.645375 m </span></span>
