Answer:
Explanation:
Initial moment of inertia of the earth I₁ = 2/5 MR² , M is mss of the earth and R is the radius . If ice melts , it forms an equivalent shell of mass 2.3 x 10¹⁹ Kg
Final moment of inertia I₂ = 2/5 M R² + 2/3 x 2.3 x 10¹⁹ x R²
For change in period of rotation we shall apply conservation of angular momentum law
I₁ ω₁ = I₂ ω₂ , ω₁ and ω₂ are angular velocities initially and finally .
I₁ / I₂ = ω₂ / ω₁
I₁ / I₂ = T₁ / T₂ , T₁ , T₂ are time period initially and finally .
T₂ / T₁ = I₂ / I₁
(2/5 M R² + 2/3 x 2.3 x 10¹⁹ x R²) / 2/5 MR²
1 + 5 / 3 x 2.3 x 10¹⁹ / M
= 1 + 5 / 3 x 2.3 x 10¹⁹ / 5.97 x 10²⁴
= 1 + .0000064
T₂ = 24 (1 + .0000064)
= 24 hours + .55 s
change in length of the day = .55 s .
Answer:
work done is -150 kJ
Explanation:
given data
volume v1 = 2 m³
pressure p1 = 100 kPa
pressure p2 = 200 kPa
internal energy = 10 kJ
heat is transferred = 150 kJ
solution
we know from 1st law of thermodynamic is
Q = du +W ............1
put here value and we get
-140 = 10 + W
W = -150 kJ
as here work done is -ve so we can say work is being done on system
Answer:
The number of crates is 84580.
Explanation:
mass, m = 30 kg
height, h = 0.9 mm
Power, P = 0.5 hp = 0.5 x 746 W = 373 W
time, t = 1 minute = 60 s
Let the number of crates is n.
Power is given by the rate of doing work.
Force, pressure, and charge are all what are called <em>derived units</em>. They come from algebraic combinations of <em>base units</em>, measures of things like length, time, temperature, mass, and current. <em>Speed, </em>for instance, is a derived unit, since it's a combination of length and time in the form [speed] = [length] / [time] (miles per hour, meters per second, etc.)
Force is defined with Newton's equation F = ma, where m is an object's mass and a is its acceleration. It's unit is kg·m/s², which scientists have called a <em>Newton</em>. (Example: They used <em>9 Newtons</em> of force)
Pressure is force applied over an area, defined by the equation P = F/A. We can derive its from Newtons to get a unit of N/m², a unit scientists call the <em>Pascal</em>. (Example: Applying <em>100 Pascals </em>of pressure)
Finally, charge is given by the equation Q = It, where I is the current flowing through an object and t is how long that current flows through. It has a unit of A·s (ampere-seconds), but scientist call this unit a Coulomb. (Example: 20 <em>Coulombs</em> of charge)
