Answer:
The toy's energy is 18 J.
Explanation:
We have, a 4 kg toy is lifted off the ground and falls at 3 m/s. It is required to find toy's energy.
The toy will have kinetic energy due to its motion. The energy is given by :
So, the toy's energy is 18 J.
Answer: Yes
Explanation:
does hot air rise
er substances, expands when heated and contracts when cooled. Because there is more space between the molecules, the air is less dense than the surrounding matter and the hot air floats upward. This is the concept used in the hot air balloons.
Answer:
6.02 radian
Explanation:
At 12 noon position is zero radian on Monday
at 12 midnight the position is π/2
at 11 am position on Tuesday is 2π/24 x 23 ( after 23 hours ) = 6..02 radian.
Answer:
Gwen’s assumption of asteroid hit as long term change is incorrect. Asteroid hit is not a long term change, instead, it is a short term change.
Explanation:
Examples of short term changes are drought, flood, volcanic eruption, etc. A short term change occurs quickly and can immediately affect organisms but it doesn’t become a reason for species extinction. The effects of a short term change don’t prevail over a long span of time.
Examples of long term changes are ice age, global warming, deforestation, etc. Unlike a short term change, it takes time but the consequences are far-reaching. It can lead to species extinction.
In this question, asteroid hit is a quick and unexpected hazard, unlike the slow long term environmental changes.
Answer:
The acceleration of Abbie is half of the Zak's.
Explanation:
The centripetal acceleration of an object on a circular path is given by :
Two children are riding on a merry-go-round that is rotating with a constant angular speed. Let 
is distance of Abbie from the merry-go-round and 
is distance of Zak's from the merry-go-round. Acceleration of Abbie is :
...... (1)
Acceleration of Zak's is :
.......(2)
Dividing equation (1) and (2) we get :
So, the acceleration of Abbie is half of the Zak's.
