Alex is asked to move two boxes of books in contact with each other and resting on a rough floor. He decides to move them at the same time by pushing on box A with a horizontal pushing force FP = 8.9 N. Here, A has a mass mA = 10.2 kg and B has a mass mB = 7.0 kg. The contact force between the two boxes is FC. The coefficient of kinetic friction between the boxes and the floor is 0.04. (Assume FP acts in the +x direction.)

Explanation:

The force of friction acting on the system

= .04 x 9.8 ( 10.2 + 7 )

= 6.74 N

Net force = 8.9 - 6.74

= 2.16 N

Acceleration in the system

= 2.16 /  ( 10.2 + 7 )

= .12558 m / s ²

Contact force between boxes = FP

Considering force on box A

Net force = 8.9 - FP

Applying Newton's law on box A

8.9 - FP = 10.2 x .12558

= 1.28

FP = 8.9 - 1.28

= 7.62 N

waves moving from a fast medium to a slow medium will experience a reflection as light travels more slowly than red light. total internal reflection occurs when the critical angle is.

u can delete ur account.

1. go on google and write

2 open this and click on your profile pic and if your profile is not appearing, then u have to log in.

3. when u click on your profile pic, there appears four options on the top.

4. click on the 1st option and scroll down and go at the bottom.

5. click on edit profile.

6. there appears a option 'prefernces' and at that option at the right side , 'edit' is written.

7. click on the edit option.

8. there is a option " i want to delete my account" and click on that.

hope this u

and ur welcm

: )