That Organ is be percussion.
Answer:
0.765m
Explanation:
gravitational potential energy GPE = mass * acceleration due to gravity * height
Given
GPE = 30Joules
Mass m = 4kg
acceleration = 9.8m/s²
Required
Height h
From the formula
h = GPE/mg
h = 30/4(9.8)
h = 30/39.2
h = 0.765m\
Hence the height of the counter is 0.765m
The answer is letter C.Weight (on Earth) is the force due to the mass of Earth attracting whatever mass is subject of discussion.
The force of attraction between any two masses is called Newton's Law of Universal Gravitation:


is simply a given constant.
If we're at the surface of Eath,

refers to the mass of the Earth,

to the mass of whatever is on the surface of Earth, and

to the radius of Earth.
Normally, we define a constant

to be equal to

; in which

is the mass of Earth and

the radius of earth;

happens to be around 9.8.
By that, we adapt the Law of Universal Gravitation to objects on the surface of Earth, we call that force Weight.

As you can see, weight is directly proportional to mass, more mass implies more weight.
If the object has a lower density it will float and it if it has a higher density it will sink, different liquids may also be heavier or lighter causing a different outcome.