Answer:
Part a)

Part b)

Part c)

Part d)

Part e)

Part f)

Explanation:
As we know that initial velocity of the ball is given as


Now final velocity of the system is given as

Part a)
now magnitude of initial momentum is given as



Part b)
Change in momentum is given as



Part c)
As we know that average force is defined as the rate of change in momentum
so here we have



Part d)
Magnitude of change in momentum is given as



Part e)
As we know that in 2nd case the force is same as the initial force
so we will have



Part f)
Since this is elastic collision so change in kinetic energy must be ZERO

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.
Http://www.emc2-explained.info/Speed-Frequency-and-Wavelength/
Answer:
The position x, is ± 0.4 m.
Explanation:
The total mechanical energy of the oscillatory motion is given as;

When the kinetic energy (E) is half of the elastic potential energy (U);

Equate (1) and (2)

Thus, the position x, is ± 0.4 m.
<h2>
Answer: The Big Bang theory</h2>
Explanation:
The Big Bang theory explains that billions of years ago, before the current universe was born, matter was concentrated in an infinitely small and highly dense point. Then, a large explosion caused this matter to expand in all directions, creating the universe we now know (including space and time).
In addition, this theory explains that our universe still continues its expansion process.