Because it has not been proven. We have no evidence that the big bang happened.
The type of motion in which a object travels in a straight line, and it’s velocity remains constant alongside that line, as it covers in equal intervals of time & irrespective of the duration of the time.
*Fig is Attached with answer*
Answer:
(a) Weight = Normal Force = 196.2 N
(b) Normal force table on 20 kg box = 294.3 N
Normal force 20 kg box on 10 kg box = 98.1 N
Explanation:
(a) Mass = m = 20 kg g = 9.81 m/s²
Weight = w = mg
w = 20 × 9.81
w = 196.2 N
As the box rests on the table so, normal force (NF) must be equal to the weight of the box.
NF = w = 196.2 N
(b)
m₁ = 20 kg m₂ = 10 kg
total mass = M = 30 kg
Total Weight = W = Mg
= 30 × 9.81
= 294.3 N
As both the boxes rest on the table so, normal force (NF) must be equal to the total weight of the boxes.
NF = W = 294.3 N
Weight of 10 kg box = 10 × 9.81 = 98.1 N
As the 10 kg box is placed on the top of 20 kg box, So 20 kg box must exert a normal force that is equal to the weight of 10 kg box.
Normal Force = Weight of 10 kg box = 98.1 N
Photosynthesis is a good one you can really explain with pictures