Answer:
The rise in height of combined block/bullet from its original position is 0.45m
Explanation:
Given;
mass of bullet, m₁ = 12 g = 0.012 kg
mass of block of wood, m₂ = 1 kg
initial speed of bullet, u₁ = 250 m/s.
initial speed of block of wood, u₂ = 0
From the principle of conservation of linear momentum, calculate the final speed of the combined block/bullet system.
m₁u₁ + m₂u₂ = v(m₁+m₂)
where;
v is the final speed of the combined block/bullet system.
0.012 x 250 + 0 = v (0.012 + 1)
3 = v (1.012)
v = 3/1.012
v = 2.96 m/s
From the principle of conservation of energy, calculate the rise in height of the block/bullet combined from its original position.
¹/₂mv² = mgh
¹/₂v² = gh
¹/₂ (2.96)² = (9.8)h
4.3808 = 9.8h
h = 4.3808/9.8
h = 0.45 m
Therefore, the rise in height of combined block/bullet from its original position is 0.45m
Answer:
426.84 m
Explanation:
initial velocity u = 0
time t = 3.3 s
distance travelled s = 53.4 m
acceleration due to gravity = g
s = ut + 1/2 g t²
53.4 = 0 + 1/2 g x 3.3²
g = 9.8 m /s²
For the whole length of fall
distance travelled = h
total time = 6.6 + 3.3 = 9.9 s
h = ut + 1/2 g t²
u again = 0
h = .5 x 9.8 x 9.9²
= 480.24 m
distance travelled in last 6.6 s
= 480.24 - 53.4
= 426.84 m
Use the formula below for this question:

re-arrange to solve for a:

now simply plug in your variables and there's your answer :). If you ever get stuck, you can look up the kinematic equations!
The gravitational forces between the Earth and Moon are greatest when the two bodies are closest together. That happens every 27.32 days, when the Moon is at the perigee of its orbit.
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But it doesn't happen at the same time in every orbit ... the Moon's perigee precesses around its orbit, on account of the gravitational forces toward the Earth, the Sun, Venus, Mars, and the other planets.