Answer:
71.8 N
Explanation:
T = Tension force in the strap
W = net work done = 752 J
f = force of friction = 8 N
d = displacement = 15 m
θ = angle between tension force and horizontal displacement = 36 deg
work done by frictional force is given as
W' = - f d
Work done by the tension force is given as
W'' = T d Cos36
Net work done is given as
W = W' + W''
W = T d Cos36 - f d
752 = T (15) Cos36 - (8) (15)
T = 71.8 N
<span>The rate at which energy is transferred is called "power."</span>
The acceleration and distance is related to the following expression:
y=v0*t + a*t^2/2 ; v0=0
y=44.1*100/2 = 2205m
hence, the speed will be
v=0 + a*t = 441m/s
from that height it will just be subjected to the gravitational acceleration
0=v_acc^2 -2g*y_free
y_free = v_acc^2/2g = 9922.5m
<span>y_max = y_acc+y_free = 441+9922.5 =10363.5m</span>
6.10 x 10^9 / 3 x 10^5 = 2.033 x 10^4 seconds = 20.33 / 3.6 = nearly 6 hours
.
very interesting and amazing question u had asked but i get it...
Answer
W = Force × Displacement
- but in above case force is exerted on the men as the weight of the child × gravitational pull of earth (9.8 m/s^2) but the displacement or movement is ZERO
- there for W= F×0 =0
- so even after carrying child for 2 hours work done by the men will be zero
<u>More</u><u> </u><u>examples</u>
- a person standing straight and lifting weight
- a person carry some weight and walk in a circular path and came back to its original position.........in this case also Displacement will be zero
------------------------------------
hope it helped u buddy
