Answer:
Zero
Explanation:
It is given that,
A person swims to the other end of a 20m long pool and back.
We need to find his displacement.
Displacement = shortest path covered
He reaches at the same position as from where he has started. It means the shortest path covered is equal to 0 i.e. his displacement is zero.
i thinkits an instrument called seismograph. not sure
Answer:
The answer cannot be determined.
Explanation:
The energy of the diver when he hits the pool will be equal to its potential energy 
, and for the temperature of the pool to rise up, this energy has to be converted into the heat energy of the pool.
The change in temperature 
then will be
Where m is the mass of water in the pool, c is the specific heat capacity of water, and 
is the added heat which in this case is the energy of the diver.
Since we do not know the mass of the water in the pool, we cannot make this calculation.
1,000 watts = 1 kilowatt
2,000 watts = 2 kilowatts
3,000 watts = 3 kilowatts
4,000 watts = 4 kilowatts
<em>5,000 watts = 5 kilowatts</em>
