Answer:
1,8066 x 1024 atoms
Explanation:
1 mole of chromium contains 6,022 x 1023 atoms
so
3 moles of chromium contains 3 times as many atoms
3 x 6,022 x 1023 = 1,8 066 x 1024
Answer:
Explanation:
a)
Ff = μmgcosθ
Ff = 0.28(1600)(9.8)cos(-84)
Ff = 458.9217...
Ff = 460 N
b) ignoring the curves required at top and bottom which change the friction force significantly, especially at the bottom where centripetal acceleration will greatly increase normal forces and thus friction force.
W = Ffd
W = 458.9217(-49.4/sin(-84)
W = 22,795.6119...
W = 23 kJ
c) same assumptions as part b
The change in potential energy minus the work of friction will be kinetic energy.
KE = PE - W
½mv² = mgh - (μmgcosθ)d
v² = 2(gh - (μgcosθ)(h/sinθ))
v = √(2gh(1 - μcotθ))
v = √(2(9.8)(49.4)(1 - 0.28cot84))
v = 30.6552...
v = 31 m/s
Answer:
They can't hear an echo in small room because in it the sound can't be reflected back. For an echo of a sound to be heard,the minimum distance between the source of sound and the walls of the room should be 17.2 m.
hopw it helps
Is it Conduction. Here's my theory e<span>nergy is transferred between the earth's surface and the atmosphere by Conduction, Convection and Radiation.</span>
Explanation:
Let
and 
The sum of the two vectors is


The difference between the two vectors can be written as

