Answer:
Efficiency = 10.2 %
Explanation:
Given the following data;
Mass = 70 kg
Height = 50 m
Velocity = 10 m/s
We know that acceleration due to gravity is equal to 9.8 m/s².
To find the efficiency of energy conversion from potential to kinetic;
First of all, we would determine the potential energy;
P.E = mgh
P.E = 70 * 9.8 * 50
P.E = 34300 J
For the kinetic energy;
K.E = ½mv²
K.E = ½ * 70 * 10²
K.E = 35 * 100
K.E = 3500
Therefore, Input energy, I = 34300 J
Output energy, O = 3500 J
Next, we find the efficiency;
Efficiency = O/I * 100
Substituting into the formula, we have;
Efficiency = 3500/34300 * 100
Efficiency = 0.1020 * 100
Efficiency = 10.2 %
Answer:
<h3>After 3seconds</h3>
Explanation:
A supersonic aircraft flies at 3 km altitude at a speed of 1000 m/s on a standard day. How long after passing directly above a ground observer is the sound of the aircraft heard by the ground observer
Using the formula for calculating speed expressed as;
Speed = Distance/Time
Given;
Distance = 3km = 3000m
Speed = 1000m/s
Required
How long after passing directly above a ground observer is the sound of the aircraft heard by the ground observer (Time)
From the formula;
Time = Distance/speed
Time = 3000/1000
Time = 3seconds
Hence the sound of the aircraft is heard after 3 seconds
Nuclear energy was not developed. It has existed for as long as time has existed, that is, since the big bang.
The thing that was developed was humans' ability to USE nuclear energy, to do what we want it to do, when we want it to do it.
The reason this was first developed was to bomb the holy beans out of Japan, in order to win World War II.
Today (2020), nine of the world's nations are known to have 14,285 nuclear bombs in storage, for the same general purpose. Seven of these nations are storing 1,170 of these bombs (about 8 percent), and the USA and Russia have all the rest ... 13,035 nuclear bombs.
All nine of these nations promise that they have no plan to use their bombs, they don't want to use them, it would be wrong and terrible to use them, and they will never be the first to use them, but they need to modernize their bombs so that theirs are better than anybody else's bombs, and they need to keep their bombs for as long as anybody else has any, and then maybe a little longer, just in case.
In the years after the ability to bomb the holy beans out of other people was developed, and enough equipment was built to do it 14 thousand times, the ability to use nuclear energy for other purposes was also developed. It's used now to generate electrical energy, and to do several jobs in Medical science.
Answer:
The ocean waves is a mechanical wave that transmits mechanical energy in the wave by the synchronized and repeated oscillation of the waters about an equilibrium level such that as the wave approaches the shoreline, and the water depth decreases, the height of the wave also increases reflecting the effective transmission of energy while the medium which is the water through which the wave propagates, move back and forth within a small region
Explanation:
A mechanical wave like other waves is the oscillation of a field about an equilibrium level. In mechanical waves, the field consists of the oscillating matter such that the wave transmits energy through a medium. The displacement of the medium through which the wave energy is limited such that the wave energy is conserved to travel far.
The statements about communication that is most accurate is:
A. Most body language is related to emotions and attitudes
Explanation:
We communicate with rather more than words: once we act with somebody, our body features a language
of its own. The approach we have a tendency to sit, the gestures we have a tendency to create, the approach we have a tendency to speak, what quantity eye contact we have a tendency to create all
of these are non-verbal ways that of act that impact the messages our words are causing.
