Answer:
The tension in the middle string is 3.3 N
Step-by-step explanation:
Two boxes move with same acceleration
The tension in the middle string is T
Lets start with the forces acting in the 2nd box
→ The tension T in the string in the direction of motion
Due to Newtons's Law
→ ∑ Force in direction of motion = mass × acceleration
→ T = M a
→ M = 1 kg
Substitute the value of M is the equation
→ T = a ⇒ (1)
The force acting on the 1st box
→ The force F in the direction of motion, and T in the string in opposite
direction of motion
→ F - T = 2M a
→ F = 10 N , M = 1 kg
Substitute These values in the equation
→ 10 - T = 2(1) a
→ 10 - T = 2 a ⇒ (2)
Substitute equation (1) in (2)
→ 10 - T = 2 T
Add T to both sides
→ 10 = 3 T
Divide both sides by 3
→ T = 3.3 N
The tension in the middle string is 3.3 N