A wooden box is sitting on a table. The normal force on the box from the table is 75 N. A second identical box is placed on top of the first box. The normal force on the first box by the table will(A) decrease.                (B) remain at 75 N.(C) increase to 150 N   (D) increase to    300 N.

Grade:upto college level

1 Answers

Navjyot Kalra
askIITians Faculty 654 Points
7 years ago
The correct option is: (c) increased to 150 N.
The normal force on the wooden box sitting on the table is 75 N, but when another identical block is placed over it, the net weight acting on the ground is the sum of the weight of the first block and the second block.
Since the block rest on the table, the magnitude of the normal force is equal to the magnitude of weight. Therefore when the second object is kept over the first, the net weight on the ground is equal to the sum of the weight of each object.
Therefore the normal force in this case would increase from 75 N to 2 (75 N) that is 150 N.
Thus (c) is the correct option, while the others are ruled out.