Correct option: B
The water is a precious resource as it is used everywhere. Once we use the water it becomes dirty or unusable and can only be recycled by snow melting or rainfall. Clean water can get used up and it can only be replenished by rain or snow melting. Hence, Penelope was correct when she said that water (clean) can be used up. If you use water for washing, cleaning and other industrial purposes, it becomes dirty and you cannot reuse it. Hence, you have to wait for rain to get clean water again. Hence, the clean water can be used up.
Answer:
s= 8.28×10⁻¹⁶m
Explanation:
given
V= 2.25×10³V
from conservation of energy
mv²/2=qΔV
v=√(2qΔV/m)
v= √(2×1.6×10⁻¹⁹×2.25×10³/9.1×10⁻³¹)
=√7.9×10¹⁴m/s
=2.8×10⁷m/s
the deflection of electron beam is
S= gt²/2
recall t= d/v
s=g(
)²/2
s= 
×9.8×(0.364/2.8×10⁷)²
s= 8.28×10⁻¹⁶m
Explanation:
If a diver ascends too quickly, the nitrogen gas in his body will expand at such a rate that he is unable to eliminate it efficiently, and the nitrogen will form small bubbles in his tissues. This is known as decompression sickness, and can be very painful, lead to tissue death, and even be life threatening.
Answer:
v = 66.7 m/s
Explanation:
Given that,
The length of steel cable, L = 600 m
Diameter = 1.2 cm
It is observed that it took 18 s for the pulse to return.
The time taken to cover 600 m will be :
t = T/2
t = 9 s
Let v be the of the pulse. We know that,
So, the speed of the pulse is equal to 66.7 m/s.
Answer:
v= 300 m/s
Explanation:
Given that
altitude ,h= 4500 m
The mass ,m = 3 kg
Lets take acceleration due to gravity , g= 10 m/s²
The speed before impact at sea level = v
Initial speed ,u = 0 m/s
We know that
v²=u²+2 g h
v=final speed
u=initial speed
h=height
Now by putting the values in the above equation
v² = 0²+ 2 x 10 x 4500
v²=90000
v= 300 m/s
Therefore the speed at sea level will be 300 m/s.
