Answer:
3560.36 Watts
Explanation:
Power,
where P is power, n is the number of skiers, t is time in seconds and Δt is change in time, ΔW is given by mgh where m is mass, g is gravitational constant, h is height
Substituting n for 4 skiers, m for 62.9 Kg, g for 9.81, h for 148 m and t for 1.71*60=102.6 seconds
P=
Average power is approximately 3560.36 Watts
Answer:
E = 13.2 kWh
, Cost = $ 10.8
Explanation:
We can look for the consumed energy from the expression of the power
P = W / t
The work is equal to the variation of the kinetic energy, for which
P = E / t
E = P t
look for the energy consumed in one day and multiply by the days of the month in the month
E = 110 4 30
E = 13200 W h
E = 13.2 kWh
the cost of this energy is
Cost = 0.9 12
Cost = $ 10.8
On Earth, the acceleration of gravity is 9.8 m/s² downward.
So any object with only gravity acting on it gains 9.8 m/s of
downward speed every second.
If the rock starts out moving upward at 10 m/s, then it will
continue upward for only (10/9.8) = 1.02 second, before
it stops rising and starts falling.
Its average speed during that time is (1/2) (10 + 0) = 5 m/s .
At an average speed of 5 m/s for 1.02 sec,
the rock rises
(5 m/s) x (1.02 sec) = 5.102 meters .
Answer:
The speed of the shell at launch and 5.4 s after the launch is 13.38 m/s it is moving towards the Earth.
Explanation:
Let u is the initial speed of the launch. Using first equation of motion as :

a=-g

The velocity of the shell at launch and 5.4 s after the launch is given by :

So, the speed of the shell at launch and 5.4 s after the launch is 13.38 m/s it is moving towards the Earth.