one disadvantage is that magnets the opposites attract so the same type of magnets like n+n will keep repelling unless you use the opposite side of the magnet the it will attract
Answer:
Explanation:
Due to change in the position of 3 kg mass , the moment of inertia of the system changes , due to which angular speed changes . We shall apply conservation of angular momentum , because no external torque is acting .
Initial moment of inertia I₁ = M R² = 3 x 1 ² = 3 kg m²
Final moment of inertia I₂ = M R² = 3 x .3 ² = 0.27 kg m²
Applying law of conservation of angular momentum
I₁ ω₁ = I₂ ω₂
Putting the values ,
3 x .75 = .27 x ω₂
ω₂ = 8.33 rad / s
New angular speed = 8.33 rad /s .
Answer:
It is (1/5)th as much.
Explanation:
If we apply the equation
F = G*m*M / r²
where
m = mass of a man
M₀ = mass of the planet Driff
M = mass of the Earth
r₀ = radius of the planet Driff
r = radius of the Earth
G = The gravitational constant
F = The gravitational force on the Earth
F₀ = The gravitational force on the planet Driff
g = the gravitational acceleration on the surface of the earth
g₀ = the gravitational acceleration on the surface of the planet Driff
we have
F₀ = G*m*M₀ / r₀² = G*m*(5*M) / (5*r)²
⇒ F₀ = G*m*M / (5*r²) = (1/5)*F
If
F₀ = (1/5)*F
then
W₀ = (1/5)*W ⇒ m*g₀ = (1/5)*m*g ⇒ g₀ = (1/5)*g
It is (1/5)th as much.
Answer:
The depth of focus achievable with those lenses is small.
Explanation:
A larger aperture makes it much harder to focus on more than one object. When using a telephoto lens (the ones the question is referring to), the depth of focus is very small. For example, using a telephoto lens to take a photo of a runner might get the runner in focus, but certainly not the track, or the audience behind them. If you look at photos, especially older photos, of Olympians in almost any sport you can see this.
Hope this helps!
