Answer:
The velocity
Explanation:
The difference between speed and velocity is the following:
- Speed is defined as the ratio between the total distance covered by an object and the time taken:
and it is a scalar.
In this problem, we cannot calculate the speed of the car, because we don't know exactly what is the distance covered by the car (we only know the distance between town A and town B, but we don't know if the car has travelled on a straight path or not, so we don't know the distance it has covered)
- Velocity is defined as the ratio between the displacement and the time taken:
(note that velocity is a vector)
Displacement is the shortest distance (straight line) between the final and the initial point of the motion: in this case, it corresponds to the distance between town A and town B, which we know. Since we also know the time of the trip, this means that we can calculate the velocity of the car.
Answer:
As b ∝ (L/r²) and
the distance of the sun from the earth is 0.00001581 light years
and
the distance of the Sirius from the earth is 8.6 light years
hence,
the Sun appear brighter in the sky
Explanation:
The brightness (b) is directly proportional to the Luminosity of the star (L) and inversely proportional to the square of the distance between the star and the observer (r).
thus, mathematically,
b ∝ (L/r²)
now,
given
L for sirius is 23 times more than the sun i.e 23L
now,
the distance of the sun from the earth is 0.00001581 light years
and
the distance of the Sirius from the earth is 8.6 light years
thus,
using the the relation between conclude that the value of brightness for the Sirius comes very very low as compared to the value for brightness for the Sun.
hence, the sun appears brighter
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
Answer:
They both produce heat energy.
