Argon: 1s22s22p63s23p6 is right answer,
Answer:
There are 146 neutrons in Uranium-238
There are 90 electrons in Thorium-234
The specific heat capacity of sand is much less than water because of which sands require less energy to cool down and similarly less energy to be heated... because of this it feels like sands absrob heat faster than water
Answer:
a) 250 N
b) 50 N
c) 5000 J
d) 4
e) 3.33
Explanation:
Given that weight of piano (
) = 1000 N, distance moved by pulley (
) = 5 m and the rope used (
) =20 m
a) The effort applied (
) if it was an ideal machine is:

b) If the actual effort = 300 N
The force to overcome friction = actual effort -
= 300 - 250 = 50 N
c) Work output = 
d) ideal mechanical advantage (IMA) = 
e) Input force = 300 N, Therefore:
actual mechanical advantage =
/ input force = 1000 / 300 = 3.33