Answer:
A frictional force acts on it
There are several approaches. The most favourable one (in my opinion) is this one:
1. Asking a question
2. Doing a research (how to answer this question)
3. Creating a hypothesis (NOT a thesis!)
4. Experimenting (to prove the hypothesis)
5. Analysing results from the experiment
6. Writing a thesis
It is gonna be C 0.37 and 19.1
Answer:
d = 19.796m
Explanation:
Since the ball is in the air for 4.02 seconds, the ball should reach the maximum point from the ground in half the total time, therefore, t=2.01s to reach maximum height. At the maximum height, the velocity in the y-direction is 0.
So we know t=2.01, vi=0, g=a=9.8m/s and we are solving for d.
Next, you look for a kinematic equation that has these parameters and the one you should choose is:

Now by substituting values in, we get
d = 19.796m
<h3>
Answer:</h3>
539.56 Joules
<h3>
Explanation:</h3>
- Efficiency of a machine is the ratio of work output to work input expressed as a percentage.
- Efficiency = (work output/work input) × 100%
- Efficiency of a machine is not 100% because so energy is lost due to friction of the moving parts and also as heat.
In this case;
Efficiency = 94%
Work input = 574 Joules
Therefore, Assuming work output is x
94% = (x/574 J) × 100%
0.94 = (x/574 J)
<h3>x = 539.56 J</h3>
Thus, you get work of 539.56 J from the machine