Answer:
B. Spring balance - a device used for measuring the weight or force of gravity acting on an object.
Explanation:
A Force is any interaction that changes the motion or position of an obkpjectbthatbit is interacting with. Whenever there is an interaction between two objects, there is a force exerted by each of the objects on one themselves.
Forces are generally divided into contact forces and non-contact over field forces.
In contact forces, the two objects physically in contact with each other. Examples of contact forces are push or pull forces, frictional forces, tensional forces, spring forces, etc.
Non-contact forces are forces in which the two objects interacting do no need to be physically in contact with one another. Examples include, gravitational forces, magnetic forces, electrical forces, etc.
Instruments used in measuring forces are known as force gauges.
From the instruments listed above:
A. A ruler is an instrument used in measuring length
B. Spring balance is a device used for measuring the weight or force of gravity acting on an object.
C. A thermometer is an instrument used in measuring temperature
D. A windbvane is an instrument used in measuring wind direction.
<h3><u>Answer;</u></h3>
Find the number of 1-foot cubes that fill the fish tank
<h3><u>Explanation;</u></h3>
Volume of a cuboid such as the fish tank is given by the product of length width and height;
Such that; Volume = length × width × height
Similarly, we can count the number of 1 foot cube that can fill the fish tank.
And since each cube has a volume of 1 cubic ft, then the number of cubes will be equivalent to the volume of the fish tank in cubic ft.
Force acting on the body when the body is at rest the net formals is given
If the.pressure exerted by a gas at [math]25^{\circ} \mathrm{C}[/math] in a volume of 0.044 L is 3.81 atm, how many moles of gas are present
Answer:
3.11 is the pH of the buffer
Explanation:
The pH of a buffer is obtained using H-H equation:
pH = pKa + log [Conjugate base] / [Weak acid]
<em>Where pH is the pH of the buffer, pKa = -log Ka = 3.14 for the citric buffer and [] could be taken as the moles of each species.</em>
The citric acid,HX (Weak acid), reacts with NaOH to produce sodium citrate, NaX (weak base) and water:
HX + NaOH → H2O + NaX
That means the moles of NaOH added = Moles of sodium citrate produced
And the resulitng moles of HX = Initial moles - Moles NaOH added
<em>Moles HX and NaX:</em>
Moles NaOH = 0.100L * (0.65mol / L) = 0.065 moles NaOH = Moles NaX
Moles HX = 0.300L * (0.45mol / L) = 0.135 moles HX - 0.065 moles NaOH = 0.070 moles HX
Replacing in H-H equation:
pH = 3.14 + log [0.065mol] / [0.070mol]
pH = 3.11 is the pH of the buffer
