Answer:
Work done is 882000joule.
power is 29400watt.
Explanation:
given,
Mass(m)=500kg
Acceleration due to gravity(g)=9.8m/s²
Height(h)=6m
Time taken(t)=30s
Workdone=?
Power=?
now,
workdone=force*displaxement
= m*g*h
=500*9.8*6
=8,82,000joule
so, the work done by the man is 8,82,000joule.
then,
power=workdone/time taken
=8,82,000/30
=29,400watt
so, the required power to lift a load is 29,400watt.
<h3>Answer</h3>
option B)
19N
<h3>Explanation</h3>
If the object is at equilibrium, then the net force acting upon the object should be 0 N. Thus, if all the forces are added together, horizontal and vertical forces separately, then the resultant force (the vector sum) should be 0 Newton.
As we only need to find the magnitude of x-component of force F
so find all x component/horizontal forces acting on the object.
50cos(40) - 40cos(25) + 30cos(55) + x = 0
38.30 - 36.25 + 17.21 + x + = 0
19.26 + x = 0
x = - 19.26
x ≈ 19 (magnitude only)
The correct choice is Buffers.
Buffers contains both acids and bases in equilibrium.when base is added to buffers, they adjust the pH value by releasing hydrogen ions.when acid is added to buffers, they adjust the pH value by consuming hydrogen ions. hence these substances resist any change in their pH value by releasing or absorbing hydrogen ions.This process keeps the pH value constant.
decomposing water does not require High activation energy
