Always Say Less Than Necessary

Why is the reading of a mercury barometer always less than actual pressure?

A mercury barometer always reads less than actual pressure.

In succelents respiratory quotient is always less than one because of

Assertion : Emissivity of any body (e) is always less than its absorptive power (a). Reason : Both the quantities are dimensionless.

Assertion(A) : Heat of neutralisation is always less than zero. Reason(R ) : Neutralisation involves reactions between an acid and a base.

in a plane progaressive harmonic wave particle speed is always less than the wave speed if.

Is the sum of m terms of an AP always less than the sum of (m +1) terms? Give reason.

Is it correct to say that bond order always increases when an electron is lost?

Assertion: Terminal potential difference of a cell is always less than its emf. Reason: Potential drop on internal resistance of cell increases terminal potential difference.