Answer:
Maximum amount of heat = 10002151.38J
Explanation:
Workdone by motor in 86.1 minutes I given by:
W = power × time
W= 294 × 86.1×60
W= 1439424 Joules
W= 1.4 ×10^6Joules
The amount of heat extracted is given by:
/QL /= K/W/ = TL/W/ /(TH - TL)
Where TL= freezing compartment temperature
TH = Outside air temperature
/QL /= 271 × 1439424 / (310 - 271)
/QL/ = 390083904/39
/QL/ = 10002151.38 Joules
The period of the wave would be halved
Answer:
39.7 m
Explanation:
First, we conside only the last second of fall of the body. We can apply the following suvat equation:

where, taking downward as positive direction:
s = 23 m is the displacement of the body
t = 1 s is the time interval considered
is the acceleration
u is the velocity of the body at the beginning of that second
Solving for u, we find:

Now we can call this velocity that we found v,
v = 18 m/s
And we can now consider the first part of the fall, where we can apply the following suvat equation:

where
v = 18 m/s
u = 0 (the body falls from rest)
s' is the displacement of the body before the last second
Solving for s',

Therefore, the total heigth of the building is the sum of s and s':
h = s + s' = 23 m + 16.7 m = 39.7 m
The radius, r, of the child from the center of the wheel is
r = 1.3 m
The wheel makes one revolution in 4.2 s. Its angular velocity is
ω = (2π rad)/(4.2 s) = 1.496 rad/s
The linear speed of the child is the tangential velocity, given by
v = rω
= (1.3 m)*(1.496 rad/s)
= 1.945 m/s
Answer: 1.95 m/s (nearest hundredth)