Answer:
Scalar quantity can never be Negative. Because scalar has only magnitude not direction. And magnitude can't be negative.
Explanation:
I think that would be c) mirror because mirrors reflects light and can't create it.
When the canoe leaked, the boat
sank because it has a leak. The boat must have a strong base at its bottom to
enable itself to float. If this is damaged, the water can now enter due to the
hole thereby increasing the velocity of water coming in.
Physical changes are those which do not affect the chemical properties of a substance. For example, when a paper is cut, the two pieces obtained are still paper. The chemical properties have not changed. Only, physically when one piece is cut to two. A chemical change occurs when the chemical properties change and a new substance with different chemical properties is obtained. For example, when the paper is burnt, it turns to ashes. Hence, this is a chemical change.
When a substance undergoes a physical change, the physical properties of the substance changes like the state (solid to liquid during melting), shape, size, volume etc. Many physical changes are reversible whereas, in general many chemical changes are irreversible.
Answer:
t = 36π seconds
Explanation:
For resolving this problem, we are going to consider a representative stadium of the United States. The Mercedes-Benz Stadium located in Atlanta, Georgia has an average radius of 90 m.
Then, its circumference measures:
L = 2πr
L = 2π(90)
L = 180π m
First, we estimate the wave's velocity: the average width of an person is 0.5 m, then the velocity is:
v = x/t
Where x: person's width
t: time
v = 0.5/0.1 = 5 m/s
The time required for the pulse to make one circuit around the stadium is:
t = x/v = 180π/5 = 36π seconds
