Answer:
In 1869 Russian chemist Dimitri Mendeleev started the development of the periodic table, arranging chemical elements by atomic mass. He predicted the discovery of other elements, and left spaces open in his periodic table for them.
Explanation:
Answer:
Cool question! First step is to find the time taken to fall
57
m
, then to find the horizontal velocity needed to cover
24
m
in that time. In this case the answer is
7.0
m
s
−
1
.
Explanation:
This is a less typical projectile motion question, but it's still projectile motion. This means the horizontal and vertical directions can be considered separately. We assume that the initial vertical velocity,
u
y
=
0
m
s
−
1
, and we are trying to find the required initial horizontal velocity,
u
x
.
To find the time taken to fall
57
m
:
s
=
u
t
+
1
2
a
t
2
Since
u
=
0
, we can rearrange this to:
t
=
√
2
s
a
=
√
2
⋅
57
9.8
=
3.41
s
The horizontal velocity will be constant (ignoring air resistance), so to cover
24
m
in
3.41
s
will be given by:
v
=
s
t
→
u
x
=
24
3.41
=
7.0
m
s
−
1
Answer link
It is generally the brightest compared to the other stars in the constellation.
Answer:
6.34×10⁹ seconds
Explanation:
Applying,
V = d/t............. Equation 1
Where V = speed plate, d = distance covered by the plate, t = time it takes the plate to travel
make t the subject of the equation
t = d/V............ Equation 2
From the question,
Given: d = 5 cm/yr = (5×3.154×10⁻⁹) = 1.577×10⁻⁸ m/s, d = 100 meter
Substitute these values into equation 2
t = 100/1.577×10⁻⁸
t = 6.34×10⁹ seconds
Hence the time it takes the the plate to travel is 6.34×10⁹ seconds
