Molten minerals inside earth is the source
So u wanna use density is mass/volume, mass can be found by a weighing scale but for volume u wanna fill a measuring cylinder with water and note the initial volume of water in it, (u can decide how much water to fill in it) and then u place the chess piece in the measuring cylinder, this will cause the water to rise and then u measure the final volume of water and do final volume - initial to find volume
Explanation:
Everyday Examples of Sliding Friction
Rubbing both hands together to create heat.
A sled sliding across snow or ice.
Skis sliding against snow.
A person sliding down a slide is an example of sliding friction.
A coaster sliding against a table.
A washing machine pushed along a floor.
An iron being pushed across material.
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 .
