Answer:
E=1760.93 cal
Explanation:
a) First we find the total time
t=x/v
t=189000/12.5
t=15120 seconds
Now we multiply the time by his total wattage
E=t*W
E=(15120)(6.5)(75)=7371000 joules
As,
1 joule = 2.389 x 10-4
So, in term of nutritional Calories
E=7371000 * 2.389*
E=1760.93 Cal
Answer:
1. The compound should be dissolved at the solvent boiling point.
2. It should be better none of the compound dissolve while at room
temperature.
3. The compound must have lower boiling point (low boiling point) than
melting point in hot solvent so to avoid it melts.
4. The compound have different solubility and impurity.
Explanation:
in order a compound to have a good crystallization, these are the primary consideration that should be followed.
1. The compound should be dissolved at the solvent boiling point.
2. It should be better none of the compound dissolve while at room
temperature.
3. The compound must have lower boiling point (low boiling point) than
melting point in hot solvent so to avoid it melts.
4. The compound have different solubility and impurity.
Answer:
Right
Explanation:
electromagnetic waves can travel through space (a vacuum) because it doesn't need a medium and its particles to propagate whereas a mechanical wave needs a medium to propagate. For example sound is a mechanical wave, sound vibrates off a mediums particles to propagate and for sound to be heard and travel
Answer:
Explanation:
To find out the angular velocity of merry-go-round after person jumps on it , we shall apply law of conservation of ANGULAR momentum
I₁ ω₁ + I₂ ω₂ = ( I₁ + I₂ ) ω
I₁ is moment of inertia of disk , I₂ moment of inertia of running person , I is the moment of inertia of disk -man system , ω₁ and ω₂ are angular velocity of disc and man .
I₁ = 1/2 mr²
= .5 x 175 x 2.13²
= 396.97 kgm²
I₂ = m r²
= 55.4 x 2.13²
= 251.34 mgm²
ω₁ = .651 rev /s
= .651 x 2π rad /s
ω₂ = tangential velocity of man / radius of disc
= 3.51 / 2.13
= 1.65 rad/s
I₁ ω₁ + I₂ ω₂ = ( I₁ + I₂ ) ω
396.97 x .651 x 2π + 251.34 x 1.65 = ( 396.97 + 251.34 ) ω
ω = 3.14 rad /s
kinetic energy = 1/2 I ω²
= 3196 J