Answer:
The answer is A. C and O..
The hypothesis because its very hard to make and it confounds me
Answer: 288.8 m
Explanation:
We have the following data:
is the time it takes to the child to reach the bottom of the slope
is the initial velocity (the child started from rest)
is the angle of the slope
is the length of the slope
Now, the Force exerted on the sled along the ramp is:
(1)
Where
is the mass of the sled and
its acceleration
In addition, if we draw a free body diagram of this sled, the force along the ramp will be:
(2)
Where
is the acceleration due gravity
Then:
(3)
Finding
:
(4)
(5)
(6)
Now, we will use the following kinematic equations to find
:
(7)
(8)
Where
is the final velocity
Finding
from (7):
(9)
(10)
Substituting (10) in (8):
(11)
Finding
:

Answer:
D. the masses of the objects and the distance between them
Explanation:
Gravitation is a force, a force doesn't care about the shape or density of objects, only about their masses... and distances.
And you can get it using the following equation:

Where :
G is the universal gravitational constant
: G = 6.6726 x 10-11N-m2/kg2
m represent the mass of each of the two objects
d is the distance between the centers of the objects.
All that business about the crane and the rope and the falling
is only there to confuse us.
The piano ended up 5 meters above the ground.
Potential energy = (mass) (gravity) (height)
= (200 kg) (9.81 m/s²) (5 m)
= (200 · 9.81 · 5) (kg-m²/s²)
= 9,810 joules .