Answer:
a) 4 b) 2 c) 8
Explanation:
Each corner of the cube is shared by 8 different cells, therefore there is 1/8 of atom for each corner. Each face of the cube is shared by 2 different cells, therefore there is 1/2 of atom for each face. Finally, each atom inside the body is not shared by different cells.
a) For face-centered cubic we have 8 corner atoms and 6 face atoms:
b) For the body-centered cubic we have 8 corner atoms and 1 atom inside the body:
c) For diamond lattice we have 8 corner atoms, 6 face atoms and 4 atoms inside the body:
Because force always has a direction, it always works towards or against something.
you might know that force,
is rate of change of momentum i.e
force = m (v-u)/t
= (mv - mu )/ t
as we know momentum is a vector quantity so, the rate of change of momentum i.e Force would also be a vector quantity.
momentum = mass × velocity
velocity has a direction so,
momentum has also got a direction.
so, momentum is also a vector quantity.
There's no information to describe the DIRECTION of the motion
at any time, so I'll have to work with speed instead of velocity.
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Average speed = (total distance covered) / (time to cover the distance)
Distance covered in the first 8 seconds = 60 meters)
Distance covered in the middle 16 seconds = 240 meters
Distance covered in the last 21 seconds = 157.5 meters
Total distance covered = 457.5 meters
Time to cover the distance = 45 seconds
Average speed = (457.5 meters) / (45 seconds) = 10.17 m/s .
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Average acceleration = (change in speed) / (time for the change)
Speed at the beginning = 0
Speed at the end = 0
Change in speed = 0
Time for the change = 45 seconds
Average acceleration = 0/45 = 0 .