Answer:
Efficiency = 80%
Explanation:
Given the following data;
Work output = 240 N
Work Input = 300 N
To find the mechanical efficiency of a machine;
Substituting into the equation, we have;

Efficiency = 80%
Therefore, the mechanical efficiency of the machine is 80 percent.
Explanation:
The gravitational force equation is the following:

Where:
G = Gravitational constant = 
m1 & m2 = the mass of two related objects
r = distance between the two related objects
The problem gives you everything you need to plug into the formula, except for the gravitational constant. Let me know if you need further clarification.
Answer:
Hypothesis
Explanation:
Refer to a trial solution to a problem as a hypothesis, often called an "educated guess" because it provides a suggested outcome based on the evidence.
Answer:
at point A the ball possess pontetial energy , point B kinetic energy then point C pontetial energy
<u>Answer:</u> The weight of the object is 29.4 N
<u>Explanation:</u>
To calculate the weight of the object, we use the equation:

where,
m = mass of the object = 3 kg
g = acceleration due to gravity = 
Putting values in above equation, we get:

Hence, the weight of the object is 29.4 N