A) Agreed.
<span>b) Value agreed but units should be W (watts). </span>
<span>c) Here's one method... </span>
<span>15 miles = 24140 m </span>
<span>1 gallon of gasoline contains 1.4×10⁸ J. </span>
<span>So moving a distance of 24140m requires gasoline containing 1.4×10⁸ J </span>
<span>Therefore moving a distance of 1m requires gasoline containing 1.4×10⁸/24140 = 5800 J </span>
<span>Overcoming rolling resitance for 1m requires (useful) work = force x distance = 1000x1 = 1000J </span>
<span>So 5800J (in the gasoline) provides 1000J (overcoming rolling resistance) of useful work for each metre moved. </span>
<span>Efficiency = useful work/total energy supplied </span>
<span>= 1000/5800 </span>
<span>= 0.17 (=17%) </span>
A. True
if cold air is replacing warm air it is a cold front and vice versa.
Answer:
The linear velocity is 
Explanation:
According to the law of conservation of energy
The potential energy possessed by the hoop at the top of the inclined plane is converted to the kinetic energy at the foot of the inclined plane
The kinetic energy can be mathematically represented as
Where 
is the moment of inertia possessed by the hoop which is mathematically represented as
Here R is the radius of the hoop
is the angular velocity which the hoop has at the bottom of the lower part of the inclined plane which is mathematically represented as
Where v linear speed of the hoop's center of mass just as the hoop leaves the incline and rolls onto a horizontal surface
Now expressing the above statement mathematically
=> 
=> 
=> 
=> 
Substituting values
