Answer:
The normal force acting on the body is equal to its weight, hence;
N = W = 196N
The normal force that the 20.0-kg box exerts on the 10.0-kg box is 98N
The formula for calculating the weight of an object is expressed as:
W = mg
m is the mass of the object
g is the acceleration due to gravity.
Given the following parameters
Mass of the box = 20.0kg
a) The weight of the box = 20 * 9.8
Weight of the box = 196N
Hence the weight of the box is 196N
Note that the normal force acting on the body is equal to its weight, hence;
N = W = 196N
b) if a 10.0-kg box is placed on top of the 20.0-kg box, the total mass will be;
M = 10 + 20 = 30kg
total weight = 30 * 9.8
Total weight = 294N
Since the normal force is equal to the weight, hence W = N = 294N
Weight of the 10kg box = 10 * 9.8 = 98N
Since the 10kg box is on top of the 20kg box, hence the normal force that the 20.0-kg box exerts on the 10.0-kg box is 98N
Step-by-step explanation: