Practice MCQ Questions and answers on Physics-GK

1 Joule (J) is the MKS unit of energy, equal to the force of one Newton acting through one meter. 1 Watt is the power from a current of 1 Ampere flowing through 1 Volt.

One light year is equal to 5.88 trillion miles (6 trillion miles approx).

One parsec is the distance to an object whose parallax angle is one arc second. The radius of the Earth's orbit equals one astronomical unit (AU), so an object that is one parsec distant is 206,265 AU (or 3.26 light-years) away.

One nanometer is equal to 10 raised to the power (-9) meters.

The length of the day is determined in astronomical units.

Work and Energy have the same physical quantities.

The mole, symbol mol, is the SI unit of amount of substance of a specified elementary entity, which may be an atom, molecule, ion, electron, any other particle or a specified group of such particles; its magnitude is set by fixing the numerical value of the Avogadro constant to be exactly 6.022 141 29 × 10²³ when it is expressed in the SI unit mol^–1.

A motion that repeats itself after equal intervals of time is known as periodic motion. Examples of periodic motion are a tuning fork or motion of a pendulum if you analyze the motion you will find that the pendulum passes through the mean position only after a definite interval of time.

When an object is slowing down, the acceleration is in the opposite direction as the velocity. Thus, this object has a negative acceleration. When an object is speeding up, the acceleration is in the same direction as the velocity. Thus, this object also has a negative acceleration.

When an object is moving with constant velocity, it does not change direction nor speed and therefore is represented as a straight line when graphed as distance over time. You can also obtain an object's velocity if you know its trace over time.