Answer:
A
Explanation:
because thats what I put and got it right
-- During the time the ball is flying from the high roof to the low roof,
it's going to fall (100-25) = 75 meters.
How long does it take an object dropped from rest to fall 75 meters ?
Distance = (1/2) · (gravity) · (time)²
75 m = (4.9 m/s²) · (time)²
Time² = (75 m) / (4.9 m/s²)
Time² = 15.31 sec²
Time = √(15.31 sec²) = 3.91 seconds
So the ball has to cover the horizontal distance of 20 meters
in 3.91 seconds.
Distance = (speed) · (time)
20 m = (speed) · (3.91 sec)
Speed = (20 m) / (3.91 sec)
Speed = 5.11 m/s
Answer:
A
Explanation:
In my opinion I'm pretty sure it's A because WE DO use microwaves and x-rays as techonological uses.
Condensation is a change of state from vapour to liquid while
freezing is also a change of state, from liquid to solid. Both are
change of states.
Additionally, condensation requires
much more energy to change the state of vapor to liquid than it does it
change the state of liquid to solid.
