Explanation

The ampere, symbol A, is the SI unit of electric current.

It is defined by considering the fixed  value of the elementary charge e as 1.602 176 634 x 1019,

where the unit C is equal to As and the second is defined by Δν Cs.

Explanation

Celsius and Fahrenheit are two temperature scales.

The Fahrenheit and Celsius scales have one point at which they intersect.

They are equal at -40°C and -40°F.

Explanation

Explanation

Oxygen has 8 protons and typically 8 neutrons, giving it a mass number of 16.

Mass number = Number of protons + Number of neutrons.

Symbol: O

Atomic number: 8

Discoverers: Joseph Priestley, Carl Wilhelm Scheele

Electrons per shell: 2, 6

Discovered: 1774

Appearance: gas: colorless; liquid and solid: pale blue

Explanation

In endothermic reactions, energy in the form of heat is taken in from the surroundings.

Examples include photosynthesis and melting of ice, where heat is absorbed to proceed.

In an exothermic reaction, energy (heat) is released/evolved to the surroundings.

Examples include combustion of fuels and respiration.

Explanation

Frequency is the number of occurrences of a repeating event per unit of time.

SI unit hertz (Hz)

In SI base units: s−1

Derivations from other quantities: f = 1 / T

Dimension T^−1

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Explanation

The SI unit of acceleration is meters/second^2 (m/s^2 or ms^-2)

Acceleration (a) is defined as the rate of change of velocity.

Velocity is a vector quantity, and therefore acceleration is also a vector quantity.

Explanation

pH stands for "Potential Hydrogen"

Blood is normally slightly basic, with a normal pH range of about 7.35 to 7.45.

Usually, the body maintains the pH of blood close to 7.40.

Acidosis is characterized by a pH of 7.35 or lower. Alkalosis is characterized by a pH level of 7.45 or higher.

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Explanation

After “prefer … to”, the verb takes the -ing form.

Correct usage: “I prefer writing to reading.”

Explanation

Newton's first law of motion is also called as Law of inertia.

• Inertia is the ability of a body by virtue of which it opposes a change.
  
• According to Newton’s first law of motion, an object will remain at rest or in uniform motion in a straight line
• unless acted upon by an external force.
  • The inertia of rest: When a body is in rest, it will remain at rest until we apply an external force to move it. This property is called inertia of rest.
  • The inertia of motion: When a body is in a uniform motion, it will remain in motion until we apply an external force to stop it. This property is called inertia of motion.