Answer: C. Radio-controlled toy airplane
Explanation:
Just did the quiz
Answer:

Explanation:
a. Internal energy and the relative specific volume at
are determined from A-17:
.
The relative specific volume at
is calculated from the compression ratio:

#from this, the temperature and enthalpy at state 2,
can be determined using interpolations
and
. The specific volume at
can then be determined as:

Specific volume,
:

The pressures at
is:

.The thermal efficiency=> maximum temperature at
can be obtained from the expansion work at constant pressure during 

b.Relative SV and enthalpy at
are obtained for the given temperature with interpolation with data from A-17 :
Relative SV at
is

=
Thermal efficiency occurs when the heat loss is equal to the internal energy decrease and heat gain equal to enthalpy increase;

Hence, the thermal efficiency is 0.563
c. The mean relative pressure is calculated from its standard definition:

Hence, the mean effective relative pressure is 674.95kPa
<span> B. A person moving a ball through a stream of water</span>
There is one mistake in the question.The Correct question is here
A cat falls from a tree (with zero initial velocity) at time t = 0. How far does the cat fall between t = 1/2 and t = 1 s? Use Galileo's formula v(t) = −9.8t m/s.
Answer:
y(1s) - y(1/2s) = - 3.675 m
The cat falls 3.675 m between time 1/2 s and 1 s.
Explanation:
Given data
time=1/2 sec to 1 sec
v(t)=-9.8t m/s
To find
Distance
Solution
As the acceleration as first derivative of velocity with respect to time
So
acceleration(-g)= dv/dt
Solve it
dv = a dt
dv = -g dt
v - v₀ = -gt
v= dy/dt
dy = v dt
dy = ( v₀ - gt ) dt
y(1s) - y(1/2s) = ( v₀ ) ( 1 - 1/2 ) - ( g/2 )[ ( t1)² -( t1/2s )² ]
y(1s) - y(1/2s) = ( - 9.8/2 ) [ ( 1 )² - ( 1/2 )² ]
y1s - y1/2s = ( - 4.9 m/s² ) ( 3/4 s² )
y(1s) - y(1/2s) = - 3.675 m
The cat falls 3.675 m between time 1/2 s and 1 s.