Solved Physics Questions For University Freshers

Q1. Define the terms Fundamental and derived quantities, giving examples of each

Solution Q1.

Fundamental quantities: These are basic physical quantities. They are so primary in themselves​​ that they require no other quantity to define them e.g Length (distance), Mass, Time, Temperature and current etc.

Derived quantities: These are secondary quantities that define nature. They are secondary in that they depend on other quantities (fundamental quantities) e.g Area, Volume, Density, Acceleration etc​​ 

Q2.​​ Convert 450KJ/hr to watts

Solution Q2.​​ Power (Watts) =​​ Workt​​ =​​ Js ​​​​ = Js-1​​ 

 ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​​​ 450×1031hr ​​ ​​​​ =​​ 450×1033600 ​​ ​​​​ =​​  ​​ 12.5w​​ 

 ​​​​ 

 ​​ ​​ ​​​​ Q3​​ Newton’s law of universal gravitation is given by F =​​ GM1M2​​ 

 ​​ ​​ ​​ ​​​​ R2

Where F,​​ is the gravitational force of attraction between the masses M1​​ and M2. ​​ Compute the dimension of gravitation G

 ​​ ​​​​ ​​ Solution Q3  ​​ ​​ ​​ ​​​​ ​​ F =​​ GM1M2R2​​ = F= ma = kgm-2=​​ MLT-2​​ 

​​ G =?

M1M2 ​​ = M.M = M2 ​​ ​​​​ R2​​ = L.L =L2

Therefore, G=​​ FR2M1M2 ​​​​ =​​ MLT-2.LM.M​​ =  ​​​​ L3T-2M-1

   G = M-1L3T-2

Q4​​ From the above equation, compute the unit of G in S.I Units

Solution Q4  ​​ ​​ ​​​​ G = M3S-2Kg-1​​ ​​ Or  ​​​​ Kg-1M3S-2