Answer:
The Mass of a person is calculated to be 28.6kg .
Explanation:
This is based on Kinetic energy and we know, that Kinetic energy is the energy possessed by body by virtue of its motion .
It can be calculated by expression :
K.E=1/2mv²
Velocity of a person = 11.2m/sec
Kinetic energy = 1800J
Mass of person = ?
We know ,
K.E=1/2mv²
so, putting values we have :
1800=1/2 x m x (11.2)²
That is ,
m=1800 x 2 /11.2 x 11.2
or
m=3600/125.44
m = 28.6 kg
Solution:
We have,
Power [P] = 25000 Watt
Mass [m] = 6000 kg
Height [h] = 20 metres
Time [t] = ?
Now,
P = W/t = F x d/t = mxgx h/t
Or, 25000 = 6000 x 10 x 20/25000 [.......g = 10
m/s^2]
Or, t = 6000 x 10 x 20/25000
Or, t = 1200/25
Therefore, t = 48 second
Hence, the required time for the crane to lift the load is 48 seconds.
Answer:
Explanation:
I can conclude that this means that the law can be broken under certain coditions as long as its not focused on a natural phenomonon
and a pheononmono is a fact or situation that is observed to exist or happen, especially one whose cause or explanation is in question.
There are two ways to solve this problem. First we write the given.
Given: Force F = 400 N; Height h = 0.5 m; Time t = 2 s
Formula: P = W/t; but Work W = Force x distance or W = f x d
Weight is also a Force, therefore: W = mg, solve for Mass m = ?
m = w/g m = 400 N/9.8 m/s² m = 40.82 Kg
P = W/t = F x d/t = mgh/t P = (40.82 Kg)(9.8 m/s²)/2 s
P = 100 J/s or 100 Watts
