Answer:

Explanation:
we know that



as we see that 
relative error
Where X_1 IS HEIGHT OF ROCK
IS THE HEIGHT OF ROAD
= uncertainity in measuring distance

Putting all value to get uncertainity in angle

solving for
we get

Though the hot cocoa would have a higher temperature, the lake would have more thermal energy because it has more molecules with a greater total internal energy.
Answer:
The student hears the wave that is transmitted by the desk
Explanation:
Mechanical waves need a material medium to be able to be transmitted, in the case of sound waves, one of the most common media is air, but it is also transmitted in other media in this case, stationery is transmitted.
The student hears the wave that is transmitted by the desk
The speed of the wave is proportional to the density of the material, so the wave that the student hears arrives much faster through the desk than through the air
The sun has orbited along time so when they ask theses questions I give you the right answer I think lol
Answer:
Explanation:
During the swing , the center of mass will go down due to which disc will lose potential energy which will be converted into rotational kinetic energy
mgh = 1/2 I ω² where m is mass of the disc , h is height by which c.m goes down which will be equal to radius of disc , I is moment of inertia of disc about the nail at rim , ω is angular velocity .
mgr = 1/2 x ( 1/2 m r²+ mr²) x ω²
gr = 1/2 x 1/2 r² x ω² + 1/2r² x ω²
g = 1 / 4 x ω² r + 1 / 2 x ω² r
g = 3 x ω² r/ 4
ω² = 4g /3 r
= 4 x 9.8 / 3 x .25
= 52.26
ω = 7.23 rad / s .