Answer
given,
Tension of string is F
velocity is increased and the radius is not changed.
the string makes two complete revolutions every second
consider the centrifugal force acting on the stone
= 
now centrifugal force is balanced by tension
T =
From the above expression we can clearly see that tension is directly proportional to velocity and inversely proportional to radius.
When radius is not changing velocity is increasing means tension will also increase in the string.
Answer:
Explanation:
Given that,
Pressure, P = 1 atm = 101325 Pa
Area of the square surface, A = 10² = 100 m²
We need to find the mass of vertical column of air. We know that, pressure is equal to the force acting per unit area. So,
So, the required mass of the vertical column of air is 
.
Answer:
D. Frozen water is less dense than liquid water.
Explanation:
Titanic sank in the North Atlantic Ocean in the year 1912. There were more than 2000 passengers on board from which about 1500 died.
Frozen water that is ice has less density than liquid water. The density of ice is 
and the density of the water is 
.
Due to this very slight difference in density, ice floats on water. Titanic, on the night of April 14, 1912, crashed into an iceberg around midnight which caused opening of 5 of its watertight compartments. The water filled into the ship and it eventually sank in.
After 20 s, the motorcycle attains a speed of
and it continues at this speed for the next 40 s. So at 45 s, its speed is 80 m/s.
It would be spectral class M
hope this helps
