Answer:
5080.86m
Explanation:
We will divide the problem in parts 1 and 2, and write the equation of accelerated motion with those numbers, taking the upwards direction as positive. For the first part, we have:
We must consider that it's launched from the ground (
) and from rest (
), with an upwards acceleration 
that lasts a time t=9.7s.
We calculate then the height achieved in part 1:
And the velocity achieved in part 1:
We do the same for part 2, but now we must consider that the initial height is the one achieved in part 1 (
) and its initial velocity is the one achieved in part 1 (
), now in free fall, which means with a downwards acceleration 
. For the data we have it's faster to use the formula 
, where d will be the displacement, or difference between maximum height and starting height of part 2, and the final velocity at maximum height we know must be 0m/s, so we have:
Then, to get 
, we do:
And we substitute the values:
Answer:
60 boxes
Explanation:
The work done by lifting a single box is equal to the force applied (the weight of the box) times the displacement of the box:
Power is related to the work done by the equation:
where W is the work done and t is the time. In this problem, we are told that the power used is P=60.0 W, while the time taken is t = 1 min = 60 s, so the total work done must be
Therefore, the number of boxes that she has to lift in order to use this power is the total work divided by the work done in lifting each box:
3. Millions of years ago, the Earth was not divided into 7 continents. It was only a very large land mass, the scientists named that one land mass “Pangaea”
4. If the tectonic plates are disturbed, they can cause mass earthquakes and tsunamis.
5. The ring of fire is a massive collection of volcanoes under the pacific ocean. They all form the shape of a ring, hence the name.
SORRY, I COULDNT ANSWER THE FIRST TWO QUESTIONS.
Answer:
Explanation:
Hello,
In this case, since we compute the required energy via:
Whereas m is the mass which here is 70 g, C the specific heat which for water is 4.184 J/(g°C) and ΔT is the temperature difference which is:
Therefore, the energy turns out:
Best regards.
Answer:
c Like/same signs
Explanation:
A repelling force occurs between two or more charged objects with the charges are of like or same sign.
- According to Coulombs law, like charges repel on another, unlike charges attracts on another.
- If a positive charge comes into the vicinity of another positive charge, there will be repulsion.
- When oppositely charge species are brought near each other, there is an attraction.
Therefore, repulsion occurs when like charges are brought close to each other.
