Answer:
To achieve the velocity of 40 m/sec height will become 4 times
Explanation:
We have given initially truck is at rest and attains a speed of 20 m/sec
Let the mass of the truck is m
At the top of the hill potential energy is mgh and kinetic energy is 
So total energy at the top of the hill 
At the bottom of the hill kinetic energy is equal to and potential energy will be 0
So total energy at the bottom of the hill is equal to 
Form energy conservation 
, for v = 20 m/sec
Squaring both side
h = 20.408 m
Now if velocity is 0 m/sec
h = 81.63 m
So we can see that to achieve the velocity of 40 m/sec height will become 4 times
Answer:
Newton's third law of motion says, "For every action there is an equal and opposite reaction." So that applied to the student's roller coaster, between the marble and the track. When the marble went up and down the hill, it created different forces onto the track.
Explanation:
mark as brainiest
You oughtta be able to do this one.
The "efficiency" is just the portion of the input work that
comes out in a useful form.
If the efficiency is 70%, that tells you that however much work
you put INto the machine, the machine will do 70% of that much
work for you at the output side.
Put 20,000 J in ... out comes (0.70) x (20,000 J) = 14,000 J .
What happens to the other 30% of the work you put into it ?
It turns into HEAT. That's why machines always have to be
cooled somehow while they're running.
Answer: Each player is responsible for all decisions in her half of the Court. She should be completely honest on all “calls” but, if in doubt, she should give her opponent the benefit of the doubt and play the ball as good. You should not play a let.
Explanation:
