laws of motion

how do i find velocity of c

15 Replies

@Gyro Gearloose

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¹¹⁷sos•7mo ago

if m is the masss yaha par a aur b kya hai

hardcoreisdeadOP•7mo ago

My bad fig nahi dala

hardcoreisdeadOP•7mo ago

Anyone ....?

Slembash•7mo ago

i m getting option a i realised late it was multicorrect soryy😅 maybe taking it T/2 in constraint equation, u might get an ans...not sure!

Ishizora•6mo ago

hardcoreisdeadOP•6mo ago

Sorry but I don't really get what uve done here

Ishizora•6mo ago

Step 1 : Make fbds of a , b and string 
Step 2 : Conclude that string ( 2T ) acts as an opposing force on block b and block a moves up the incline due to ( 3 T ) 
Step 3 : Apply string constraint i.e sum of Tension and (velocity/acceleration)'s dot product should be equal to zero                                                                       - Applying s/c to find velocity of block a :     (-2T) ( 3 ) + 3T( V ) = 0 ; V = 2 m/s
- Applying the same to find acc of block a :      (-2T) ( 6 ) + 3T ( a ) = 0 ; a = 4m/s^2
Step 4 : Checking relative motion 
- Vel of b wrt a = 3-2 = 1 m/s  
- Acc of b wrt a = 6-4 = 2 m/s^2
Step 5 : Calculating Velocity at point C  
( Velocity/acceleration of pulley is the avg of motion of string at ends of it )
- It is evident that string on left of it is going up with velocity the same as block a so 2 m/s and the pulley is going up with velocity the same as block b so 3 m/s. 
      3 = ( V at C + 2 ) / 2 ; V at C = 4 m/s

Step 1 : Make fbds of a , b and string 
Step 2 : Conclude that string ( 2T ) acts as an opposing force on block b and block a moves up the incline due to ( 3 T ) 
Step 3 : Apply string constraint i.e sum of Tension and (velocity/acceleration)'s dot product should be equal to zero                                                                       - Applying s/c to find velocity of block a :     (-2T) ( 3 ) + 3T( V ) = 0 ; V = 2 m/s
- Applying the same to find acc of block a :      (-2T) ( 6 ) + 3T ( a ) = 0 ; a = 4m/s^2
Step 4 : Checking relative motion 
- Vel of b wrt a = 3-2 = 1 m/s  
- Acc of b wrt a = 6-4 = 2 m/s^2
Step 5 : Calculating Velocity at point C  
( Velocity/acceleration of pulley is the avg of motion of string at ends of it )
- It is evident that string on left of it is going up with velocity the same as block a so 2 m/s and the pulley is going up with velocity the same as block b so 3 m/s. 
      3 = ( V at C + 2 ) / 2 ; V at C = 4 m/s