Answer: Base units
The principal SI units that are used to derive all other SI units are called base units. The base units are the units of fundamental quantities e.g. M L T that is Mass, Length, and Time. All other physical quantities can be written in the fundamental dimension forms. The physical quantities are not measured directly but are build up from the building blocks that are the fundamental quantities which have base units.
Answer by mimiwhatsup: B) Velocity is a vector and requires a direction to completely describe it.
Velocity is the speed and direction of an object in motion.
The air would contract therefore the answer is the second choice.
Answer:
O The particles of the medium move more slowly and there are fewer chances to transfer energy.
Explanation:
Various media are made up of particles. These particles are in constant motion according to the kinetic theory of matter. Recall that temperature has been defined as the average kinetic energy of the particles in a medium. Hence, for any given medium, the velocity of particle motion increases or decreases linearly with temperature.
The speed of particles in any medium increases or decreases as the temperature of the medium increases or decreases as emphasised above. Hence, at low temperature, the velocity of waves set up by the motion of particles in a medium decreases and transfer the wave energy to neighbouring particles occurs more slowly than at high temperatures.
Answer:
B = 4.059 x 10¹⁵ T
Explanation:
Given,
Number of loop, N = 400
radius of loop, r = 0.65 x 10⁻¹⁵ m
Current, I = 1.05 x 10⁴ A
Magnetic field at the center of the loop


B = 4.059 x 10¹⁵ T