A 55.5kg mass, measuring 545 N in weight is lifted to a height of 12.5m in 2.75s. Calculate the work done on?

Question

this weight.
A. Calculate the power produced in lifting this weight to that height.
B. Calculate the potential energy of this weight at the maximum height
C. Calculate the kinetic energy of this weight just before impact on the ground.
D. Calculate the velocity of this weight just before impact.
any help with these will be greatly appreciated.

Answer 1

The work done on the weight is:
W = mgh = (545 N)*(12.5) = 6813 J

a)
The power is the energy expended (6813 J) divided by the time it took to do it:
P = W / t = (6813 J) / (2.75 s) = 2477 J/s = 2477 watts

b)
Defining the potential energy of the weight at the floor level to be zero, the potential energy of the weight at its maximum height is:
U = mgh = W = 6813 J

c)
The conservation of energy says that the sum of the potential and kinetic energies is constant. So if you drop the mass from height h, the initial kinetic and potential energies are:
Ki = 0
Ui = 6813 J
Just before it hits the ground, the potential energy is zero, so the kinetic energy must be:
K = 6813 J
in order to satisfy the conservation of energy.

d)
The kinetic energy of the mass is given by the equation:
K = ½mv²
and we know the value just before impact (6813 J), so we can find its velocity just before impact:
K = ½mv²
v² = 2K/m
v = √(2K/m) = √(2*6813 / 55.5) = 15.67 m/s

Answer 2

wonderful question :) particularly using fact of your age, you certainly might desire to be careful how lots weight you utilize once you're lifting. do no longer attempt to be macho and finally end up with stunted boost ;) Be authentic to your self once you're saying you utilize mild adequate weights :) you will stunt your boost if the weights are too heavy. or you're effective. i might stay removed from supplementations that are no longer organic. i might stay removed from supplementations alltogether and locate what you like in foodstuff. Peanut butter has a super form of protein for occasion. Stuff like that. savor your self ;)

Answer 3

W = F*s = (545 N)(12.5 m) = 6,812.5 J
A. P = (545 N)(12.5 m)/(2.75 s) = 2,477.3 W
B. P.E. = (545 N)(12.5 m) = 6,812.5 J
C. K.E. = 6,812.5 J
D. V = sqrt(2*6812.5/55.5) = 15.668 m/s

Answer 4

the answer is 6