The International System Units or the SI units is scientific method of expressing the magnitudes or quantities of important natural phenomena. There are seven base units in the system, from which other units are derived. This system was formerly called the meter-kilogram-second (MKS) system.
Answer: The formula used to solve the problems related to first law of thermodynamics is 
Explanation:
First law of thermodynamics states that the total energy of the system remains conserved. Energy can neither be destroyed, nor be created but it can only be transformed into one form to another.
Its implication is any change in the internal energy will be either due to heat energy or work energy.
Mathematically,

where, Q = heat energy
W = work energy
= Change in internal energy
Sign convention for these energies:
For Q: Heat absorbed will be positive and heat released will be negative.
For W: Work done by the system is negative and work done on the system is positive.
For
: When negative, internal energy is decreasing and when positive, internal energy is increasing.
Hence, the formula used to solve the problems related to first law of thermodynamics is 
The force of impact is same for both bus and the bicycle. The acceleration of bicycle will be greater than the acceleration of bus.
<u>Explanation:</u>
The interaction that occurs between two objects refers to collision. this makes the two objects to come in contact with each other. The third law of Newton states that, when there occurs a collision between two objects, then the force that is applied on each object will be same. But, the direct in which the force is impacted will be in opposite direction.
The magnitude of the forces will be equal but the direction will not be same. The collision results in gaining the momentum by one object and losing momentum by another. The acceleration is mainly associated with the mass of the object. When the object has smaller mass, it will be accelerated more. In the given example, as bus is heavier than bicycle, the bicycle will have greater acceleration than the bus.
Answer:
m = 4
Explanation:
It is given that,
A 100 Newton force applied to a machine lifts a 400 N object.
We need to find the mechanical advantage of this machine.
The mechanical advantage of a machine is given by the ratio of output force to the input force.
Here, output force is 400 N and input force is 100 N
So, mechanical advantage becomes :

So, the mechanical advantage of this machine is 4.