Answer:
Thus, the payback time for cavity wall insulation is 7.5 years
solution:
radius of steel ball(r)=5cm=0.05m
density of ball =8000kgm
terminal velocity(v)=25m/s^2
density of air( d) =1.29 kgm
now
volume of ball(V)=4/3pir^3=1.33×3.14×0.05^3=0.00052 m^3
density of ball= mass of ball/Volume of ball
or, 8000=m/0.00052
or, m=4.16 kg
weight of the ball (W)= mg=4.16×10=41.6 N
viscous force(F)=6 × pi × eta × r × v
=6×3.14×eta×0.05×25
=23.55×eta
To attain the terminal velocity,
Fiscous force=Weight
or, 23.55× eta = 41.6
or, eta = 1.76
whete eta is the coefficient of viscosity.
Yes.....The continetal plates shifting would cause either disaster...
Answer:
distance = 21.56 m
Explanation:
given data
mass = 50 kg
initial velocity = 18.2 m/s
force = -200 N ( here force applied to opposite direction )
final velocity = 12.6 m/s
solution
we know here acceleration will be as
acceleration a = force ÷ mass
a =
= -4 m/s²
we get here now required time that is
required time =
...............1
put here value
required time =
so distance will be
distance =
........2
distance =
distance = 21.56 m
I can't answer this question without a figure. I've found a similar problem as shown in the first picture attached. When adding vectors, you don't have to add the magnitudes only, because vectors also have to factor in the directions. To find the resultant vector C, connect the end tails of the individual vectors.
<em>The red line (second picture) represents the vector C.</em>