Question

8.
In the arrangement shown, what is the normal
reaction between the block A (mass = 5 kg) and
ground?
(1) 50 N
(3) 30 N
(2) 20 N
(4) Zero​

Answer 1

Answer:

☆points to note before solving:-

• tension will appear in string due to gravitational force on the 2kg block
• tension(T) will be same throughout the string(massless)
• Fnet=Fdriving-Fopposing=ma
• acceleration will be 0 here,as for normal rxn block should be in contact with ground.

● 2kg block

: mg - T = ma

mg - T = 0

T=mg=2g

●5kg block

: N + T = mg

N + 2g = 5g

N = 3g= 30N

( normal is result of total pressing force )

hope it helps!