Question

two objects Aand B have masses in the ratio of 2:1 and are dropped from the same height. 1.What is the ratio of velocities of A nd B? 2.What is theratio of forces of A and B when they strike a ground? explain the reason.........plz answer it ASAP I have my exam on Saturday

Answer 1

1} the velocities will be same because the value of acceleration due to gravity will be same
2}F=mass*acceleration
so , ratio of force of object A to B is
Fa/Fb=2x*a/1x*a
so ratio of forces will also be same i.e. 2:1
welcome

Answer 2

Remains same

2 : 1

Explanation:  Using the equation of motion:  v = u + at

           For 1st body, a = g, u = 0

⇒ v₁ = 0 + gt₁    ⇒ v₁ = gt₁

           For 2nd body, a = g, u = 0

⇒ v₂ = 0 + gt₂    ⇒  v₂ = gt₂

Using, S = ut + 1/2 at²,

⇒ S₁ = 0(t) + g(t₁)²/2   ⇒ S₁ =  g(t₁)²/2

⇒ S₂ = 0(t) + g(t₂)²/2   ⇒ S₂ =  g(t₂)²/2

  But since they are dropped form same height, S₁ = S₂:

⇒ g(t₁)²/2 = g(t₂)²/2

⇒ t₁ = t₂    

Hence,  v₁ = gt₁  &  v₂ = gt₂

 v₁ = gt₁ = gt₂ = v₂      [t₁ = t₂]

(ii)   F = ma  , let masses be 2x and x

For 1st body, F₁ = 2xa

For 2nd bod, F₂ = 1xa = ax

Ratio of forces = (2xa):(xa) = 2 : 1