1. Law of conservation of energy states that energy cannot be created, nor destroyed, for example, windmills take kinetic energy(movement energy) and convert it into electrical energy using gears and a generator as well as the blades.
so this supports it because the pendulum never reaches the same height twice unless you reset it so the energy is always getting less and less and not randomly getting back onto the pendulum.
2.Gravity, friction and air resistance slow it down as well
3. at the top, potential energy is the amount of energy something has relative to the amount it can disperse before stopping, for example, a book on a shelf has more potential energy than that of a book on a table, this is because when the shelf book falls it will create more energy than the table book.
Question 9 is 100 N.
Question 10 is No, the bike's motion is not changing so it could be at rest or moving at a constant velocity.
Question 11 is Be doubled.
Question 12 is Ella is correct.
Hope i helped.
Kinetic energy is related to velocity by:
KE = (1/2)mv^2
solve for mass m
10 = (1/2)m(10)^2
10 = (1/2)m(100)
10= 50m
10/50 = m
1/5 = m
at 20 km/hr
KE = (1/2)(1/5)(20)^2
KE = (1/10)(400)
KE = 40 J
Answer:

Explanation:
Note that acceleration is the rate change of velocity i.e
.
Since the velocity is giving as a variable dependent on the pressure, we have to differentiate implicitly both side with respect to time,i.e

if we substitute value for the pressure as giving in the question and also since the rate change of pressure is 0.354psi/sec, we have

